A gear is a mechanical machine part that transmits motion by successfully engaging teeth and gives the impression of positive action by coordinating and interlocking precise effort to achieve the desired result. Gear design necessitates a thorough investigation, and the loads, as well as the gear parameters, were determined by trial and error. When a single tooth on any gear breaks, the transfer of power is halted, resulting in material, time, and cost waste. The design and development of spur gear with teeth portability is the subject of this research paper. ANSYS is used to perform gear design analysis. To ensure precision, a wire cut electric discharge machine is used to cut each tooth, which is then assembled into gear using a gear blank, cover plate, nut, and bolt. The results of the analysis performed in the program Ansys 15.0 show that the proposed portable tooth spur gear can withstand maximum principal stress of 1.1886 × 108 Pa and total deformation that will occur at this stress 5.7897 × 10(−6) m. If the portable tooth spur gear is used, the cost of replacing all 65 teeth would be about 3000 Rupees. Keeping this in mind, replacing all 65 teeth twice a year would cost about 11500 Rupees, which is less than the total cost of the traditional gear design. In comparison to the conventional gear design, the proposed design reduces long-term maintenance costs.
{"title":"Modeling and Analysis of Gear Tooth Replacement System Against Breaking of Single Tooth","authors":"Dhiren Patel, Gurpritsingh T. Virdi, A. D. Dhass","doi":"10.1115/imece2021-73316","DOIUrl":"https://doi.org/10.1115/imece2021-73316","url":null,"abstract":"\u0000 A gear is a mechanical machine part that transmits motion by successfully engaging teeth and gives the impression of positive action by coordinating and interlocking precise effort to achieve the desired result. Gear design necessitates a thorough investigation, and the loads, as well as the gear parameters, were determined by trial and error. When a single tooth on any gear breaks, the transfer of power is halted, resulting in material, time, and cost waste. The design and development of spur gear with teeth portability is the subject of this research paper. ANSYS is used to perform gear design analysis. To ensure precision, a wire cut electric discharge machine is used to cut each tooth, which is then assembled into gear using a gear blank, cover plate, nut, and bolt. The results of the analysis performed in the program Ansys 15.0 show that the proposed portable tooth spur gear can withstand maximum principal stress of 1.1886 × 108 Pa and total deformation that will occur at this stress 5.7897 × 10(−6) m. If the portable tooth spur gear is used, the cost of replacing all 65 teeth would be about 3000 Rupees. Keeping this in mind, replacing all 65 teeth twice a year would cost about 11500 Rupees, which is less than the total cost of the traditional gear design. In comparison to the conventional gear design, the proposed design reduces long-term maintenance costs.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130742725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents a design method for compensating the gravity effect of a three-degrees-of-freedom (3-DoF) hybrid robotic manipulator with variable payloads. The manipulator is constructed by a pair of 2-DoF parallelogram-based five-bar parallel mechanisms combined with a 1-DoF serial mechanism. The balancing design of the manipulator is realized by attaching two balancing units to the five-bar parallel mechanism, where each unit is made by a geared seven-bar mechanism with a linear spring. The parameters of the balancing units are analytically derived from the static equilibrium of the mechanism. The design method is also effective when the payload is varied and the spring stiffnesses are prescribed. Examples are then given to illustrate the effectiveness of the proposed method. The method was also validated by simulation software. The simulation results showed that, by using the balancing design, the actuation torques of the manipulator could be reduced by more than 98% with different applied payloads.
{"title":"Gravity Balancing Design of a 3-DOF Hybrid Robotic Manipulator With Variable Payloads","authors":"V. Nguyen","doi":"10.1115/imece2021-69857","DOIUrl":"https://doi.org/10.1115/imece2021-69857","url":null,"abstract":"\u0000 This paper presents a design method for compensating the gravity effect of a three-degrees-of-freedom (3-DoF) hybrid robotic manipulator with variable payloads. The manipulator is constructed by a pair of 2-DoF parallelogram-based five-bar parallel mechanisms combined with a 1-DoF serial mechanism. The balancing design of the manipulator is realized by attaching two balancing units to the five-bar parallel mechanism, where each unit is made by a geared seven-bar mechanism with a linear spring. The parameters of the balancing units are analytically derived from the static equilibrium of the mechanism. The design method is also effective when the payload is varied and the spring stiffnesses are prescribed. Examples are then given to illustrate the effectiveness of the proposed method. The method was also validated by simulation software. The simulation results showed that, by using the balancing design, the actuation torques of the manipulator could be reduced by more than 98% with different applied payloads.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"34 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133147086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guangsen Chen, Shi Chen, J. Schoop, J. Caudill, I. Jawahir
In this work, orthogonal cutting experiments with varying uncut chip thickness (10–50 μm) were performed under a range of sustainable (dry, MQL and cryogenic) cooling strategies to study the combined ploughing and cutting processes for Ti-6Al-4V alloy. With the increasing uncut chip thickness, from 20 μm to 50μm, the principal force increased approximately linearly from 200 N to 480 N. However, the thrust force increased only slightly from 400 N to 500 N. For the minimum uncut chip thickness (10 μm), the forces at the dry and MQL conditions generated fluctuation due to the unstable cutting process, which means that the materials accumulated ahead of cutting edge periodically due to the combined effects of sliding, ploughing and cutting. The thickness of the grain refinement layer with uncut chip thickness of 10 μm was thicker than those produced with larger uncut chip thickness, i.e., more material was ploughed to machined surface at uncut chip thickness of 10μm than those at larger uncut chip thickness conditions. The measured micro-hardness of machined surface at the uncut chip thickness of 10 μm at different cooling/lubrication conditions was about 380–395 HV, higher that those with uncut chip thickness of 50μm (350–360 HV). The increase in surface hardness at the small uncut chip thickness was mainly caused by the grain refinement related to the sever plastic deformation (SPD) due to the ploughing effect. Overall, orthogonal machining of Ti-6Al-4V alloy with cryogenic cooling and small uncut chip thickness exhibited finish machining surface integrity and mechanical behaviors.
本研究通过对Ti-6Al-4V合金进行不同切削厚度(10-50 μm)的正交切削实验，研究了连续(干式、MQL和低温)冷却策略下的犁耕和切削结合过程。毛边的芯片厚度增加,从20μm 50μm,校长力近似线性增加从200 N, 480 N, 400 N的推力仅略有增加芯片足本500 N .最小厚度(10μm),干燥和MQL条件生成的力量波动,由于不稳定的切削过程,这意味着之前积累的材料前沿定期由于滑动的联合影响,耕作和切割。当切屑厚度为10μm时，晶粒细化层的厚度比大切屑厚度条件下的晶粒细化层厚度要厚，即当切屑厚度为10μm时，加工表面被犁入的材料比大切屑厚度条件下多。不同冷却/润滑条件下，未切削切屑厚度为10 μm的加工表面显微硬度约为380 ~ 395 HV，高于未切削切屑厚度为50μm的加工表面(350 ~ 360 HV)。未切削切屑厚度小处表面硬度的提高主要是由于犁耕效应引起的严重塑性变形引起的晶粒细化所致。综上所述，Ti-6Al-4V合金低温冷却和小切屑厚度正交加工具有精加工表面完整性和力学性能。
{"title":"The Influence of Sustainable Cooling Strategies and Uncut Chip Thickness on Surface Integrity in Finish Machining of Ti-6Al-4V Alloy","authors":"Guangsen Chen, Shi Chen, J. Schoop, J. Caudill, I. Jawahir","doi":"10.1115/imece2021-73236","DOIUrl":"https://doi.org/10.1115/imece2021-73236","url":null,"abstract":"\u0000 In this work, orthogonal cutting experiments with varying uncut chip thickness (10–50 μm) were performed under a range of sustainable (dry, MQL and cryogenic) cooling strategies to study the combined ploughing and cutting processes for Ti-6Al-4V alloy. With the increasing uncut chip thickness, from 20 μm to 50μm, the principal force increased approximately linearly from 200 N to 480 N. However, the thrust force increased only slightly from 400 N to 500 N. For the minimum uncut chip thickness (10 μm), the forces at the dry and MQL conditions generated fluctuation due to the unstable cutting process, which means that the materials accumulated ahead of cutting edge periodically due to the combined effects of sliding, ploughing and cutting. The thickness of the grain refinement layer with uncut chip thickness of 10 μm was thicker than those produced with larger uncut chip thickness, i.e., more material was ploughed to machined surface at uncut chip thickness of 10μm than those at larger uncut chip thickness conditions. The measured micro-hardness of machined surface at the uncut chip thickness of 10 μm at different cooling/lubrication conditions was about 380–395 HV, higher that those with uncut chip thickness of 50μm (350–360 HV). The increase in surface hardness at the small uncut chip thickness was mainly caused by the grain refinement related to the sever plastic deformation (SPD) due to the ploughing effect. Overall, orthogonal machining of Ti-6Al-4V alloy with cryogenic cooling and small uncut chip thickness exhibited finish machining surface integrity and mechanical behaviors.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133232899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Rehekampff, Benedikt Kirchebner, F. Krebs, F. Irlinger, Tim C. Lueth
In Material Jetting, build material is deposited as single droplets onto a platform. This offers potential advantages such as faster processing and cheaper raw material compared to powder based processes. For metals, this technology is subject of several research projects. Due to variations in droplet size, the process inevitably results in deviations between the desired and the actual height of a printed layer. Such deviations can add up over several layers and thus lead to an unacceptably high overall geometrical deviation of the component. One possible solution to this problem is the compensation of local height deviations by adjusting the build strategy (droplet size, droplet spacing) in the next layer. For this, it is necessary to measure the geometric deviations of the local layer heights. However, the temperatures of up to 300 °C inside the build chamber pose a challenge for the integration of a measuring system. In this work, a process monitoring system was integrated into a previously developed printer for Material Jetting of aluminum. The system consists of an optical confocal sensor that enables contactless distance measurement. To avoid overheating of the sensor, it is located outside the build chamber. An infrared filter glass allows measurement from the outside, while heat radiation from the build platform is absorbed by the glass. The sensor is water cooled to ensure a safe operating temperature. A calibration object and printed aluminum components were measured to validate the system. The measurement results show the potential of the system for inline process monitoring for Material Jetting. Based on this, the development of a closed-loop layer height control is now possible.
{"title":"Inline Topology Measurement of Material Jetted Metal Parts","authors":"C. Rehekampff, Benedikt Kirchebner, F. Krebs, F. Irlinger, Tim C. Lueth","doi":"10.1115/imece2021-70279","DOIUrl":"https://doi.org/10.1115/imece2021-70279","url":null,"abstract":"\u0000 In Material Jetting, build material is deposited as single droplets onto a platform. This offers potential advantages such as faster processing and cheaper raw material compared to powder based processes. For metals, this technology is subject of several research projects. Due to variations in droplet size, the process inevitably results in deviations between the desired and the actual height of a printed layer. Such deviations can add up over several layers and thus lead to an unacceptably high overall geometrical deviation of the component.\u0000 One possible solution to this problem is the compensation of local height deviations by adjusting the build strategy (droplet size, droplet spacing) in the next layer. For this, it is necessary to measure the geometric deviations of the local layer heights. However, the temperatures of up to 300 °C inside the build chamber pose a challenge for the integration of a measuring system.\u0000 In this work, a process monitoring system was integrated into a previously developed printer for Material Jetting of aluminum. The system consists of an optical confocal sensor that enables contactless distance measurement. To avoid overheating of the sensor, it is located outside the build chamber. An infrared filter glass allows measurement from the outside, while heat radiation from the build platform is absorbed by the glass. The sensor is water cooled to ensure a safe operating temperature.\u0000 A calibration object and printed aluminum components were measured to validate the system. The measurement results show the potential of the system for inline process monitoring for Material Jetting. Based on this, the development of a closed-loop layer height control is now possible.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121993500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As a relatively complex part of aero-engine turbine blades, the integral impeller is characterized by complex space, high steepness, and distortion. An actual five-axis computerized numerical control (CNC) machining process unaffected by the machining quality and accuracy of a large curvature range. Consequently, knowing how to reasonably adjust the feed speed of a path in view of further improving the efficiency has always been difficult. This research adopts the method of combining computer-aided manufacturing (CAM) and CNC and proposes a direct interpolation algorithm for the double non-uniform rational B-spline curves based on the typical characteristics of the integral impeller. First, in the CNC, the integral impeller is divided into high-speed regions and three-dimensional characteristic parameters of the integral impeller in CAM. Second, in the low-speed area, the feature-divided high- and low-speed areas are discretized on the basis of the interpolation period and equal arc length. Then, the low-speed area speed is adjusted to meet the kinematic constraints according to the dichotomous configuration. Finally, the discrete speed is smoothly filtered by the Finite Impulse Response (FIR) filter to be able to meet the dynamic response characteristics of the machine tool. Simulations and experiments show that the algorithm can effectively improve the speed and smoothness of the inlet and exhaust edges of the overall impeller, effectively reduce the calculation amount of the numerical control system, and improve the overall machining efficiency of the impeller under the requirements of machining accuracy.
{"title":"Efficient Feedrate Optimization Method for Spline Toolpath Based on Typical Characteristics of Integral Impeller","authors":"Jianxin Xiao, Bingran Li, Jun Fang, Hui Zhang","doi":"10.1115/imece2021-68728","DOIUrl":"https://doi.org/10.1115/imece2021-68728","url":null,"abstract":"\u0000 As a relatively complex part of aero-engine turbine blades, the integral impeller is characterized by complex space, high steepness, and distortion. An actual five-axis computerized numerical control (CNC) machining process unaffected by the machining quality and accuracy of a large curvature range. Consequently, knowing how to reasonably adjust the feed speed of a path in view of further improving the efficiency has always been difficult. This research adopts the method of combining computer-aided manufacturing (CAM) and CNC and proposes a direct interpolation algorithm for the double non-uniform rational B-spline curves based on the typical characteristics of the integral impeller. First, in the CNC, the integral impeller is divided into high-speed regions and three-dimensional characteristic parameters of the integral impeller in CAM. Second, in the low-speed area, the feature-divided high- and low-speed areas are discretized on the basis of the interpolation period and equal arc length. Then, the low-speed area speed is adjusted to meet the kinematic constraints according to the dichotomous configuration. Finally, the discrete speed is smoothly filtered by the Finite Impulse Response (FIR) filter to be able to meet the dynamic response characteristics of the machine tool. Simulations and experiments show that the algorithm can effectively improve the speed and smoothness of the inlet and exhaust edges of the overall impeller, effectively reduce the calculation amount of the numerical control system, and improve the overall machining efficiency of the impeller under the requirements of machining accuracy.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126110483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kunlin Yang, Rui Chen, Zeeshan Qaiser, Shane Johnson
Custom manufacturing of freeform surfaces, such as that of sheet metal components for automobiles, or the body panels and the composite parts of aircraft provides major challenges for traditional dedicated manufacturing systems (DMSs) due to the following factors: (1) mass customization, (2) rapid prototyping, (3) time and personnel cost, and (4) system complexity. Typically, flexible manufacturing systems (FMSs) and reconfigurable manufacturing systems (RMSs) are designed for fixed and high variability in the design parameters resulting in high system complexity. These design methodologies have many opportunities stemming from some limitations including: (1) lacking feature analysis of high variability products, (2) high system complexity, (3) reduced capacity for manufacturing of high curvature surfaces, and/or (4) low repeatability. An extended Multi-actuated Optimized Reconfigurable Freeform Surface (e-MORFS) mold is developed for a targeted application for the mass production of the freeform surfaces, e.g. custom foot orthoses (CFOs). The e-MORFS mold aims at the following goals: (1) to achieve size and shape variability for a complex product with a large population, (2) to reduce system complexity considering product features, and (3) to achieve high curvature surface reconstruction with proper boundary conditions (BCs) to avoid wrinkling and stretching. The e-MORFS mold achieves the maximum error range of 0.3–0.5mm for the whole population with only 6 actuators. This study provides the e-MORFS mold and design algorithm potentially used for targeted application of freeform surface manufacturing, e.g. CFOs. These design methodologies may guide designs of freeform surface manufacturing in applications, e.g. automobile, aerospace, biomechanics, and architecture.
{"title":"An Extended Multi-Actuated Optimized Reconfigurable Freeform Surface (e-MORFS) Mold With Targeted Variability Capacity","authors":"Kunlin Yang, Rui Chen, Zeeshan Qaiser, Shane Johnson","doi":"10.1115/imece2021-71248","DOIUrl":"https://doi.org/10.1115/imece2021-71248","url":null,"abstract":"\u0000 Custom manufacturing of freeform surfaces, such as that of sheet metal components for automobiles, or the body panels and the composite parts of aircraft provides major challenges for traditional dedicated manufacturing systems (DMSs) due to the following factors: (1) mass customization, (2) rapid prototyping, (3) time and personnel cost, and (4) system complexity. Typically, flexible manufacturing systems (FMSs) and reconfigurable manufacturing systems (RMSs) are designed for fixed and high variability in the design parameters resulting in high system complexity. These design methodologies have many opportunities stemming from some limitations including: (1) lacking feature analysis of high variability products, (2) high system complexity, (3) reduced capacity for manufacturing of high curvature surfaces, and/or (4) low repeatability. An extended Multi-actuated Optimized Reconfigurable Freeform Surface (e-MORFS) mold is developed for a targeted application for the mass production of the freeform surfaces, e.g. custom foot orthoses (CFOs). The e-MORFS mold aims at the following goals: (1) to achieve size and shape variability for a complex product with a large population, (2) to reduce system complexity considering product features, and (3) to achieve high curvature surface reconstruction with proper boundary conditions (BCs) to avoid wrinkling and stretching. The e-MORFS mold achieves the maximum error range of 0.3–0.5mm for the whole population with only 6 actuators. This study provides the e-MORFS mold and design algorithm potentially used for targeted application of freeform surface manufacturing, e.g. CFOs. These design methodologies may guide designs of freeform surface manufacturing in applications, e.g. automobile, aerospace, biomechanics, and architecture.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129955712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effect of the grinding process for weld flash removal on the surface integrity of the welded joint has not been researched. The surface integrity of the welded joint is essential for the bandsaw blade life and to prevent any premature failure at the weld joint due to fatigue loading (a band saw blade undergoes mainly cyclic bending fatigue during its service). In this study, the effects of using different cutting fluid combinations on the grinding of weld flash in medium carbon alloy steel were carried out. The use of compressed air as a sustainable solution for grinding weld flash was explored. Experimental investigation of four different cutting fluid applications (dry/no cutting fluid, compressed air, minimum quantity lubricant using vegetable oil, and minimum quantity coolant used water-soluble oil) was carried out. Aluminum oxide grinding wheel at constant cutting speed was used for the study. The surface roughness, sub-surface residual stresses, and microhardness of the ground region were measured for all experimental conditions. This is a first-of-the-kind study on the effect of the flash removal process on the surface integrity of the welded joint. The results show that the surface integrity of the welded joint is significantly influenced by the cutting fluid application used during the grinding process of the flash. This research indicates that it is essential to use cutting fluid during the grinding process of the weld flash. Dry grinding, the current industry standard for grinding weld flash in band saw blades, produced tensile residual stresses, had the highest subsurface thermal damage, and produced the highest surface roughness. In contrast, the sustainable solutions suggested in this research can increase the fatigue life of the ground joint and increase the tool life of the grinding wheels. This study provides the road map for selecting the cutting fluid application for grinding weld flash produced by the resistance welding process in the band sawing industry.
{"title":"Effects of Cutting Fluid Applications on Surface Integrity in Grinding of Weld Flash in Resistance Welded Alloy Steel","authors":"Nithin Rangasamy, Chanda Sekhar Rakurty","doi":"10.1115/imece2021-69807","DOIUrl":"https://doi.org/10.1115/imece2021-69807","url":null,"abstract":"\u0000 The effect of the grinding process for weld flash removal on the surface integrity of the welded joint has not been researched. The surface integrity of the welded joint is essential for the bandsaw blade life and to prevent any premature failure at the weld joint due to fatigue loading (a band saw blade undergoes mainly cyclic bending fatigue during its service). In this study, the effects of using different cutting fluid combinations on the grinding of weld flash in medium carbon alloy steel were carried out. The use of compressed air as a sustainable solution for grinding weld flash was explored. Experimental investigation of four different cutting fluid applications (dry/no cutting fluid, compressed air, minimum quantity lubricant using vegetable oil, and minimum quantity coolant used water-soluble oil) was carried out. Aluminum oxide grinding wheel at constant cutting speed was used for the study. The surface roughness, sub-surface residual stresses, and microhardness of the ground region were measured for all experimental conditions. This is a first-of-the-kind study on the effect of the flash removal process on the surface integrity of the welded joint. The results show that the surface integrity of the welded joint is significantly influenced by the cutting fluid application used during the grinding process of the flash. This research indicates that it is essential to use cutting fluid during the grinding process of the weld flash. Dry grinding, the current industry standard for grinding weld flash in band saw blades, produced tensile residual stresses, had the highest subsurface thermal damage, and produced the highest surface roughness. In contrast, the sustainable solutions suggested in this research can increase the fatigue life of the ground joint and increase the tool life of the grinding wheels. This study provides the road map for selecting the cutting fluid application for grinding weld flash produced by the resistance welding process in the band sawing industry.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"94 29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129086277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shang Li, Can Yang, Huan Yang, Fei Peng, Xiao-Hong Yin
In this work, the femtosecond laser was used to process the surface of the 3D printed components. After femtosecond laser scanning, the scanning electron microscope (SEM) was utilized to observe the surface morphology of the samples. In addition, the laser confocal microscope (LCM) was adopted to measure the surface roughness, and the contact angle measuring instrument was employed to characterize the surface wettability. By adjusting two laser process parameters (i.e., the number of scan and scan pitch), the surface defects had been successfully eliminated and surface modification for certain application had been achieved. After laser processing, the surface roughness increases to a certain extent due to the generation of surface micro/nanostructures. Wettability experiments showed that compared with the superhydrophilicity of the original surface, the surface contact angle after laser processing increased to a certain extent, and the surface wettability had been changed. In summary, the feasibility of femtosecond laser processing for the surface of 3D printed specimens was preliminarily verified. In the future efforts, multi-parameter experiments and numerical simulation will be further carried out to achieve better post-processing effects for the 3D printed component surfaces.
{"title":"Simultaneously Eliminate Defects and Modify Surface for 3D Printed Components Using Femtosecond Laser","authors":"Shang Li, Can Yang, Huan Yang, Fei Peng, Xiao-Hong Yin","doi":"10.1115/imece2021-65947","DOIUrl":"https://doi.org/10.1115/imece2021-65947","url":null,"abstract":"\u0000 In this work, the femtosecond laser was used to process the surface of the 3D printed components. After femtosecond laser scanning, the scanning electron microscope (SEM) was utilized to observe the surface morphology of the samples. In addition, the laser confocal microscope (LCM) was adopted to measure the surface roughness, and the contact angle measuring instrument was employed to characterize the surface wettability. By adjusting two laser process parameters (i.e., the number of scan and scan pitch), the surface defects had been successfully eliminated and surface modification for certain application had been achieved. After laser processing, the surface roughness increases to a certain extent due to the generation of surface micro/nanostructures. Wettability experiments showed that compared with the superhydrophilicity of the original surface, the surface contact angle after laser processing increased to a certain extent, and the surface wettability had been changed. In summary, the feasibility of femtosecond laser processing for the surface of 3D printed specimens was preliminarily verified. In the future efforts, multi-parameter experiments and numerical simulation will be further carried out to achieve better post-processing effects for the 3D printed component surfaces.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130967755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The inspection path planning of sheet metal assemblies plays an important role in the measurement efficiency of large free-form surfaces. In the path generation of a 5-axis coordinate measurement machine (CMM), large calculation of collision detection and obstacle avoidance are needed in the traditional computer-aided inspection planning methods. Owing to structure complexity of large free-form surfaces, the planning procedures for collision detection and automatic collision-free trajectory generation is time-consuming and low-efficiency. To address this problem, a safety-space-based modeling approach is proposed to generate a feasible collision-free path for a large number of key measurement points. At first, based on the decomposition of the dynamic motion trajectory of the probe and discretizing of the inspected object, a continuous envelope space, i.e., safety space is constructed for candidate path generation of the probe. In the proposed planning strategy, the work of collision detection and avoidance are eliminated. Then, a heuristic optimization algorithm is used to generate the feasible trajectory in the constructed safety space for all the measurement points. At last, an inspection path planning case of a car door assembly was used to illustrate the procedure of the proposed method.
{"title":"A Safety-Space-Based Approach to Inspection Path Planning for the Sheet Metal Assemblies","authors":"Yinhua Liu, Chao An, Zhenxia Duan","doi":"10.1115/imece2021-68437","DOIUrl":"https://doi.org/10.1115/imece2021-68437","url":null,"abstract":"\u0000 The inspection path planning of sheet metal assemblies plays an important role in the measurement efficiency of large free-form surfaces. In the path generation of a 5-axis coordinate measurement machine (CMM), large calculation of collision detection and obstacle avoidance are needed in the traditional computer-aided inspection planning methods. Owing to structure complexity of large free-form surfaces, the planning procedures for collision detection and automatic collision-free trajectory generation is time-consuming and low-efficiency. To address this problem, a safety-space-based modeling approach is proposed to generate a feasible collision-free path for a large number of key measurement points. At first, based on the decomposition of the dynamic motion trajectory of the probe and discretizing of the inspected object, a continuous envelope space, i.e., safety space is constructed for candidate path generation of the probe. In the proposed planning strategy, the work of collision detection and avoidance are eliminated. Then, a heuristic optimization algorithm is used to generate the feasible trajectory in the constructed safety space for all the measurement points. At last, an inspection path planning case of a car door assembly was used to illustrate the procedure of the proposed method.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121319383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The primary objective of this research was to gain fundamental insight on the effect of imposed shear rates by dynamic melt modulation during injection molding on the crystallinity development of PLA. The dynamic melt modulation was achieved by a Dynamic & Intelligent Shear-Controlled Injection Molding (DISC-IM) instrument that utilized an in-house developed control system capable of oscillating the injection screw. The melt modulation process proved to be an efficient processing technique for enhanced properties in a particular commercial grade of PLA that contained various additives. The cycle time was reduced by 40% and total crystallinity was increased by ∼50% during DISC-IM as compared to the conventional injection molding under similar conditions. The oscillatory movements also promoted the formation of a phase crystalline structures on the surface layer of the samples. The crystallization behavior of neat PLA was dramatically enhanced by 1wt.% of orotic acid. Introduction of DISC-IM enhanced the crystallinity of PLA-OA blends from 25% to 56% at a mold temperature of 70°C. Although, the overall crystallinity was relatively similar for different DISC-IM conditions, the crystalline phases that were formed was different. DISC-IM process promoted the formation of á phases for PLA-OA blends.
{"title":"Enhanced Crystallinity Development of Poly-Lactic Acid by Dynamic Melt Manipulation","authors":"P. Gao, A. Kundu, K. Alqosaibi, J. Coulter","doi":"10.1115/imece2021-73392","DOIUrl":"https://doi.org/10.1115/imece2021-73392","url":null,"abstract":"\u0000 The primary objective of this research was to gain fundamental insight on the effect of imposed shear rates by dynamic melt modulation during injection molding on the crystallinity development of PLA. The dynamic melt modulation was achieved by a Dynamic & Intelligent Shear-Controlled Injection Molding (DISC-IM) instrument that utilized an in-house developed control system capable of oscillating the injection screw. The melt modulation process proved to be an efficient processing technique for enhanced properties in a particular commercial grade of PLA that contained various additives. The cycle time was reduced by 40% and total crystallinity was increased by ∼50% during DISC-IM as compared to the conventional injection molding under similar conditions. The oscillatory movements also promoted the formation of a phase crystalline structures on the surface layer of the samples. The crystallization behavior of neat PLA was dramatically enhanced by 1wt.% of orotic acid. Introduction of DISC-IM enhanced the crystallinity of PLA-OA blends from 25% to 56% at a mold temperature of 70°C. Although, the overall crystallinity was relatively similar for different DISC-IM conditions, the crystalline phases that were formed was different. DISC-IM process promoted the formation of á phases for PLA-OA blends.","PeriodicalId":113474,"journal":{"name":"Volume 2B: Advanced Manufacturing","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116513948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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