Gülsüm Topateş, Erdem Akça, Yahya Kemal Tür, Cihangir Duran
Functionally graded ceramic systems consisted of Al2O3/(Al2O3–ZrO2) and Al2O3/(Al2O3–Nd2Ti2O7) have been produced by gel casting. In Al2O3/ZrO2 systems, Al2O3 was gathered with three different Al2O3/ZrO2 mixtures with varying ZrO2 contents. For Al2O3/Nd2Ti2O7 system, Al2O3 layer was combined with 3 mol% Nd2Ti2O7‐doped Al2O3. All samples sintered at 1480 and 1540°C showed strong adhesion between layers without any crack formation. In the Al2O3/ZrO2 systems, both layers were intact; a distinct separation was observed, whereas a large reaction zone was observed for the Al2O3/Nd2Ti2O7 system as a consequence of reaction between both phases. The separation between layers for both systems was identified by SEM–EDX analyses. The hardness and wear tests of the samples showed that functional grading approach ensures combining various physical properties in a monolithic body.
{"title":"Functionally graded Al2O3‐based ceramic systems by gel casting method","authors":"Gülsüm Topateş, Erdem Akça, Yahya Kemal Tür, Cihangir Duran","doi":"10.1111/ijac.14898","DOIUrl":"https://doi.org/10.1111/ijac.14898","url":null,"abstract":"Functionally graded ceramic systems consisted of Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/(Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–ZrO<jats:sub>2</jats:sub>) and Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/(Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–Nd<jats:sub>2</jats:sub>Ti<jats:sub>2</jats:sub>O<jats:sub>7</jats:sub>) have been produced by gel casting. In Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/ZrO<jats:sub>2</jats:sub> systems, Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> was gathered with three different Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/ZrO<jats:sub>2</jats:sub> mixtures with varying ZrO<jats:sub>2</jats:sub> contents. For Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/Nd<jats:sub>2</jats:sub>Ti<jats:sub>2</jats:sub>O<jats:sub>7</jats:sub> system, Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> layer was combined with 3 mol% Nd<jats:sub>2</jats:sub>Ti<jats:sub>2</jats:sub>O<jats:sub>7</jats:sub>‐doped Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>. All samples sintered at 1480 and 1540°C showed strong adhesion between layers without any crack formation. In the Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/ZrO<jats:sub>2</jats:sub> systems, both layers were intact; a distinct separation was observed, whereas a large reaction zone was observed for the Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/Nd<jats:sub>2</jats:sub>Ti<jats:sub>2</jats:sub>O<jats:sub>7</jats:sub> system as a consequence of reaction between both phases. The separation between layers for both systems was identified by SEM–EDX analyses. The hardness and wear tests of the samples showed that functional grading approach ensures combining various physical properties in a monolithic body.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"7 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xuekun Tian, Zhenyi Zhao, Xusheng Liu, Chengliang Ma, Lei Liu, Xinhong Liu
At present, graphite is commonly used as the carbon source in Al2O3‐C refractory. However, graphite resources are limited and belong to the category of nonrenewable resources. Coconut shell is a biomass material with low cost, low impurity, and high reactivity, and also belongs to renewable resources. Therefore, the research for using coconut shell carbon as a substitution for graphite in Al2O3‐C refractory has great significance. In this work, the coconut shell was firstly carbonized at 200–1000°C in flowing argon, and the microstructure of the carbonized coconut shells was investigated. Then the carbonized coconut shell powder was introduced into Al2O3‐C refractory instead of graphite, and the effect of carbonized coconut shell on mechanical properties and microstructure evolution of materials was investigated. The results show that the carbonized coconut shell has porous structures, composed of amorphous carbon and disordered micro‐graphite with many defects, endowing its high reactivity. Compared with graphite, the carbonized coconut shell promotes the Si and Al to in situ formation of nonoxide ceramic whiskers (SiC, Al4C3, and AlN), which play a strengthening and toughening role in the materials. When graphite is replaced by 1 wt% carbonized coconut shell, the residual strength ratio of samples increased from 81.8% to 90.2%, and that of the hot modulus of rupture increased from 17.53 MPa to 18.47 MPa.
{"title":"Enhancing the mechanical properties of Al2O3‐C refractory: Carbonized coconut shell as a substitution for graphite","authors":"Xuekun Tian, Zhenyi Zhao, Xusheng Liu, Chengliang Ma, Lei Liu, Xinhong Liu","doi":"10.1111/ijac.14895","DOIUrl":"https://doi.org/10.1111/ijac.14895","url":null,"abstract":"At present, graphite is commonly used as the carbon source in Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>‐C refractory. However, graphite resources are limited and belong to the category of nonrenewable resources. Coconut shell is a biomass material with low cost, low impurity, and high reactivity, and also belongs to renewable resources. Therefore, the research for using coconut shell carbon as a substitution for graphite in Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>‐C refractory has great significance. In this work, the coconut shell was firstly carbonized at 200–1000°C in flowing argon, and the microstructure of the carbonized coconut shells was investigated. Then the carbonized coconut shell powder was introduced into Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>‐C refractory instead of graphite, and the effect of carbonized coconut shell on mechanical properties and microstructure evolution of materials was investigated. The results show that the carbonized coconut shell has porous structures, composed of amorphous carbon and disordered micro‐graphite with many defects, endowing its high reactivity. Compared with graphite, the carbonized coconut shell promotes the Si and Al to in situ formation of nonoxide ceramic whiskers (SiC, Al<jats:sub>4</jats:sub>C<jats:sub>3</jats:sub>, and AlN), which play a strengthening and toughening role in the materials. When graphite is replaced by 1 wt% carbonized coconut shell, the residual strength ratio of samples increased from 81.8% to 90.2%, and that of the hot modulus of rupture increased from 17.53 MPa to 18.47 MPa.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"7 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ZrB2–SiC ceramics are the potential candidates for the ultrahigh‐temperature thermal protection materials of sharp‐bodied reentry and hypersonic vehicles. However, their ultrahigh‐temperature mechanical behaviors have been rarely reported. In the present work, an ultrahigh‐temperature testing method for the tensile properties of ceramics is proposed. The tensile behaviors of ZrB2–20 vol% SiC are studied up to 1950°C in air and to 2050°C in nitrogen atmosphere for the first time. The tensile stress–strain curves, Young's modulus, and tensile strength are obtained. The microstructure evolutions, including crystallization of sintering aids, grain recombination, and grain oxidation, are observed, and their effects on the tensile properties are analyzed. The mechanisms controlling the tensile behaviors at ultrahigh temperatures are revealed. The maximum operating temperature of ZrB2–SiC ceramics has been identified.
{"title":"Ultrahigh‐temperature tensile behaviors of ZrB2–SiC ceramics","authors":"Tianbao Cheng, Jingwen Lv, Shuyan Nie","doi":"10.1111/ijac.14901","DOIUrl":"https://doi.org/10.1111/ijac.14901","url":null,"abstract":"ZrB<jats:sub>2</jats:sub>–SiC ceramics are the potential candidates for the ultrahigh‐temperature thermal protection materials of sharp‐bodied reentry and hypersonic vehicles. However, their ultrahigh‐temperature mechanical behaviors have been rarely reported. In the present work, an ultrahigh‐temperature testing method for the tensile properties of ceramics is proposed. The tensile behaviors of ZrB<jats:sub>2</jats:sub>–20 vol% SiC are studied up to 1950°C in air and to 2050°C in nitrogen atmosphere for the first time. The tensile stress–strain curves, Young's modulus, and tensile strength are obtained. The microstructure evolutions, including crystallization of sintering aids, grain recombination, and grain oxidation, are observed, and their effects on the tensile properties are analyzed. The mechanisms controlling the tensile behaviors at ultrahigh temperatures are revealed. The maximum operating temperature of ZrB<jats:sub>2</jats:sub>–SiC ceramics has been identified.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"76 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Silver ions possess inherent antioxidant properties, whereas hydroxyapatite (HAP) is a structural support within the body. The research methodology involves synthesizing HAP and 3% silver‐doped hydroxyapatite (Ag‐HAP) via the sol–gel method, followed by comprehensive characterization using X‐ray diffraction, Fourier transform infrared, Raman spectroscopy, and field emission scanning electron microscopy, antioxidant, thrombogenicity, and cell viability. The investigation reveals that Ag‐HAP exhibits superior antioxidant properties and thrombogenicity compared to other metals doped so far. Remarkably, Ag‐HAP demonstrates moderate clotting behavior compared to HAP. Additionally, the (3‐(4, 5‐dimethythiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide) MTT assay evaluates cellular viability, shedding light on the biocompatibility of the materials. The study uncovers the potential of silver doping to enhance the antioxidant capabilities of HAP significantly, offering promising prospects for orthopaedic implants. The antioxidant activity of the materials is evaluated through a 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging assay, whereas the thrombogenicity is assessed using a whole blood clotting method. The improvement indicates that incorporating silver ions influences HAP crystalline structure and increased grain size, contributing to enhanced antioxidant efficacy and favorable cellular responses, thus underlining the potential of Ag‐HAP for advanced implant materials in orthopaedic surgery. The results also discuss that how Ag‐HAP is better than Co‐HAP.
{"title":"Thrombogenicity, DPPH assay, and MTT assay of sol–gel derived 3% silver‐doped hydroxyapatite for hard tissue implants","authors":"Ranbir Kumar, Deep Shikha","doi":"10.1111/ijac.14884","DOIUrl":"https://doi.org/10.1111/ijac.14884","url":null,"abstract":"Silver ions possess inherent antioxidant properties, whereas hydroxyapatite (HAP) is a structural support within the body. The research methodology involves synthesizing HAP and 3% silver‐doped hydroxyapatite (Ag‐HAP) via the sol–gel method, followed by comprehensive characterization using X‐ray diffraction, Fourier transform infrared, Raman spectroscopy, and field emission scanning electron microscopy, antioxidant, thrombogenicity, and cell viability. The investigation reveals that Ag‐HAP exhibits superior antioxidant properties and thrombogenicity compared to other metals doped so far. Remarkably, Ag‐HAP demonstrates moderate clotting behavior compared to HAP. Additionally, the (3‐(4, 5‐dimethythiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide) MTT assay evaluates cellular viability, shedding light on the biocompatibility of the materials. The study uncovers the potential of silver doping to enhance the antioxidant capabilities of HAP significantly, offering promising prospects for orthopaedic implants. The antioxidant activity of the materials is evaluated through a 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging assay, whereas the thrombogenicity is assessed using a whole blood clotting method. The improvement indicates that incorporating silver ions influences HAP crystalline structure and increased grain size, contributing to enhanced antioxidant efficacy and favorable cellular responses, thus underlining the potential of Ag‐HAP for advanced implant materials in orthopaedic surgery. The results also discuss that how Ag‐HAP is better than Co‐HAP.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"29 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bingqing Yang, Xingyu Chen, Jiaxing Xie, Lijuan Huang, Xiao Wu, Chunlin Zhao, Tengfei Lin, Min Gao, Cong Lin
Antiferroelectric (AFE) Pb0.96La0.04Zr0.90Ti0.10O3 (PLZT) and AgNbO3 (AN) ceramics were fabricated codoped with 1 mol% Er and various contents of Yb3+ ions. The ceramics exhibit good energy storage performances and electric‐field‐controlled photoluminescence (E‐PL) intensity modulations, both of which are attributed to the reversible AFE‐ferroelectric phase transition that accompanies a structural evolution. Accordingly, a noncontact energy charge/discharge monitor is proposed based on the E‐PL effect, which is convenient and safe for the high‐energy density capacitors. Besides, the PLZT and AN ceramics exhibit opposite E‐PL behaviors that are caused due to different crystal space group transitions.
用 1 mol% Er 和不同含量的 Yb3+ 离子掺杂制备了反铁电（AFE）Pb0.96La0.04Zr0.90Ti0.10O3（PLZT）和 AgNbO3（AN）陶瓷。这些陶瓷表现出良好的储能性能和电场控制的光致发光（E-PL）强度调制，这两种性能都归因于伴随结构演变的可逆 AFE- 铁电相变。因此，我们提出了一种基于 E-PL 效应的非接触式能量充放电监测器，它对于高能量密度电容器来说既方便又安全。此外，PLZT 和 AN 陶瓷表现出相反的 E-PL 行为，这是由于不同的晶体空间群转变造成的。
{"title":"Energy storage behaviors and synchronously electric modulations of photoluminescence in Er/Yb‐codoped Pb0.96La0.04Zr0.90Ti0.10O3 and AgNbO3 antiferroelectrics: A noncontact charge/discharge monitoring method","authors":"Bingqing Yang, Xingyu Chen, Jiaxing Xie, Lijuan Huang, Xiao Wu, Chunlin Zhao, Tengfei Lin, Min Gao, Cong Lin","doi":"10.1111/ijac.14892","DOIUrl":"https://doi.org/10.1111/ijac.14892","url":null,"abstract":"Antiferroelectric (AFE) Pb<jats:sub>0.96</jats:sub>La<jats:sub>0.04</jats:sub>Zr<jats:sub>0.90</jats:sub>Ti<jats:sub>0.10</jats:sub>O<jats:sub>3</jats:sub> (PLZT) and AgNbO<jats:sub>3</jats:sub> (AN) ceramics were fabricated codoped with 1 mol% Er and various contents of Yb<jats:sup>3+</jats:sup> ions. The ceramics exhibit good energy storage performances and electric‐field‐controlled photoluminescence (<jats:italic>E</jats:italic>‐PL) intensity modulations, both of which are attributed to the reversible AFE‐ferroelectric phase transition that accompanies a structural evolution. Accordingly, a noncontact energy charge/discharge monitor is proposed based on the <jats:italic>E</jats:italic>‐PL effect, which is convenient and safe for the high‐energy density capacitors. Besides, the PLZT and AN ceramics exhibit opposite <jats:italic>E</jats:italic>‐PL behaviors that are caused due to different crystal space group transitions.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"21 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hao Zhang, Guixiang Liu, Bo Dai, Shuai Fu, Detian Wan, Yiwang Bao, Longsheng Chu, Qingguo Feng, Chunfeng Hu
Carbon‐bonded carbon fiber composites (CBCF) are renowned for their lightweight and thermal insulation properties. However, the brittleness and susceptibility to oxidation hinder the widespread application of CBCF. In this work, the carbon‐bonded carbon/quartz hybrid fiber composites (CBCQF) were prepared by pressure filtration and modified by Cr2AlC ceramics. The microstructure, mechanical properties, thermal insulation, and ablation behaviors were investigated. Cr2AlC ceramics notably enhanced the compressive strength of CBCQF in the XY direction and reduced the room‐temperature thermal conductivity in the Z direction. Most importantly, Cr2AlC ceramics significantly improved the ablation resistance of CBCQF. When 40% Cr2AlC ceramics were added, the linear and mass ablation rates of CBCQF were reduced by 38.0% and 93.2%, respectively, compared to the reference sample. Moreover, the study of ablation mechanisms revealed that the improvement in ablation resistance was primarily derived from the formation of the surface protective oxides as well as the reinforcement of oxidation resistance. Overall, this study presents a promising avenue for the application of Cr2AlC ceramics and the modification of fiber composites.
{"title":"Cr2AlC ceramic–modified carbon/quartz fiber composites with enhanced ablation resistance and thermal insulation","authors":"Hao Zhang, Guixiang Liu, Bo Dai, Shuai Fu, Detian Wan, Yiwang Bao, Longsheng Chu, Qingguo Feng, Chunfeng Hu","doi":"10.1111/ijac.14900","DOIUrl":"https://doi.org/10.1111/ijac.14900","url":null,"abstract":"Carbon‐bonded carbon fiber composites (CBCF) are renowned for their lightweight and thermal insulation properties. However, the brittleness and susceptibility to oxidation hinder the widespread application of CBCF. In this work, the carbon‐bonded carbon/quartz hybrid fiber composites (CBCQF) were prepared by pressure filtration and modified by Cr<jats:sub>2</jats:sub>AlC ceramics. The microstructure, mechanical properties, thermal insulation, and ablation behaviors were investigated. Cr<jats:sub>2</jats:sub>AlC ceramics notably enhanced the compressive strength of CBCQF in the <jats:italic>XY</jats:italic> direction and reduced the room‐temperature thermal conductivity in the <jats:italic>Z</jats:italic> direction. Most importantly, Cr<jats:sub>2</jats:sub>AlC ceramics significantly improved the ablation resistance of CBCQF. When 40% Cr<jats:sub>2</jats:sub>AlC ceramics were added, the linear and mass ablation rates of CBCQF were reduced by 38.0% and 93.2%, respectively, compared to the reference sample. Moreover, the study of ablation mechanisms revealed that the improvement in ablation resistance was primarily derived from the formation of the surface protective oxides as well as the reinforcement of oxidation resistance. Overall, this study presents a promising avenue for the application of Cr<jats:sub>2</jats:sub>AlC ceramics and the modification of fiber composites.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"84 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The tribological performance of the tungsten carbide substrate (WC‐Co), improved by ceramic coatings, is still being reported in new studies that have been carried out to date. It has become a hot research topic that are widely applied in hard material research, especially in the tools manufacturing fields. This study was conducted to investigate the wear characteristics of a commercial cemented carbide tool (WC‐Co) coated with a physical vapor deposition chromium‐vanadium nitride film (CrVN), followed by a boriding process as a final thermochemical treatment. Tested in dry sliding contact against an alumina ball as a static partner, the tribological responses of the specimen were analyzed and compared with an uncoated specimen. Friction coefficients, calculated from volume loss, were around .58 for all specimens except the uncoated specimen at 10 N of applied load. Wear scar analyses revealed the occurrence of several wear mechanisms that is polishing, oxidation, wear debris formation, surface binder removal, grain fragmenting, and grain pull‐out.
迄今为止，通过陶瓷涂层改善碳化钨基材（WC-Co）摩擦学性能的新研究报告仍在不断涌现。它已成为硬质材料研究中广泛应用的热门研究课题，尤其是在工具制造领域。本研究调查了一种商用硬质合金工具（WC-Co）的磨损特性，该工具涂有一层物理气相沉积铬钒氮化膜（CrVN），并在最后的热化学处理过程中进行了硼化处理。试样与氧化铝球作为静态伙伴进行了干滑动接触测试，分析了试样的摩擦响应，并与未涂层试样进行了比较。根据体积损失计算出的摩擦系数在施加 10 N 负荷时，除无涂层试样外，所有试样的摩擦系数都在 0.58 左右。磨损痕分析表明了几种磨损机制，即抛光、氧化、磨损碎屑形成、表面粘合剂去除、晶粒破碎和晶粒拉出。
{"title":"Microstructure and tribological properties of CrVN thin film coated WC‐Co tool after boriding process","authors":"Khokha Lalaoui, Mounia Belaid, Nasser Eddine Beliardouh, Kheireddine Bouzid, Samira Tlili, Latifa Kahloul, Karima Boudjeda, Chems Eddine Ramoul","doi":"10.1111/ijac.14896","DOIUrl":"https://doi.org/10.1111/ijac.14896","url":null,"abstract":"The tribological performance of the tungsten carbide substrate (WC‐Co), improved by ceramic coatings, is still being reported in new studies that have been carried out to date. It has become a hot research topic that are widely applied in hard material research, especially in the tools manufacturing fields. This study was conducted to investigate the wear characteristics of a commercial cemented carbide tool (WC‐Co) coated with a physical vapor deposition chromium‐vanadium nitride film (CrVN), followed by a boriding process as a final thermochemical treatment. Tested in dry sliding contact against an alumina ball as a static partner, the tribological responses of the specimen were analyzed and compared with an uncoated specimen. Friction coefficients, calculated from volume loss, were around .58 for all specimens except the uncoated specimen at 10 N of applied load. Wear scar analyses revealed the occurrence of several wear mechanisms that is polishing, oxidation, wear debris formation, surface binder removal, grain fragmenting, and grain pull‐out.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"43 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Digital light processing (DLP) three‐dimensional printing has the advantages of both high printing resolution and efficiency and has been used to manufacture high‐precision, small, and complex shaped ceramic parts. One of the challenges of DLP is to develop photosensitive ceramic slurries with high solid content and low viscosity, especially for non‐oxide ceramics such as silicon nitride due to the dispersion and light absorption problem. This study mainly explores the dispersibility of silicon nitride in ultraviolet (UV)‐cured resins and the photocured properties of the slurry. Rheological measurements were utilized to characterize and screen different dispersants in the resin. It was found that DISPERMP is an effective dispersant. In order to improve the curing depth of Si3N4 photosensitive paste, the surface of silicon nitride powder was treated by oxidation, and organic compounds with different refractive indices were also introduced to increase the light penetration depth. It was found that glycerol with a refractive index of 1.474 resulted in the greatest improvement in the curing depth of Si3N4 photosensitive paste. Finally, a proposed slurry composition was developed to successfully print silicon nitride ceramics through UV‐curing molding technology.
{"title":"Preparation and optimization of silicon nitride slurries for digital light processing","authors":"Qi Sha, Jianjun Xie, Yesen Duan, Wenyu Tang, Jingxian Zhang","doi":"10.1111/ijac.14888","DOIUrl":"https://doi.org/10.1111/ijac.14888","url":null,"abstract":"Digital light processing (DLP) three‐dimensional printing has the advantages of both high printing resolution and efficiency and has been used to manufacture high‐precision, small, and complex shaped ceramic parts. One of the challenges of DLP is to develop photosensitive ceramic slurries with high solid content and low viscosity, especially for non‐oxide ceramics such as silicon nitride due to the dispersion and light absorption problem. This study mainly explores the dispersibility of silicon nitride in ultraviolet (UV)‐cured resins and the photocured properties of the slurry. Rheological measurements were utilized to characterize and screen different dispersants in the resin. It was found that DISPERMP is an effective dispersant. In order to improve the curing depth of Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> photosensitive paste, the surface of silicon nitride powder was treated by oxidation, and organic compounds with different refractive indices were also introduced to increase the light penetration depth. It was found that glycerol with a refractive index of 1.474 resulted in the greatest improvement in the curing depth of Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> photosensitive paste. Finally, a proposed slurry composition was developed to successfully print silicon nitride ceramics through UV‐curing molding technology.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"14 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yunsong Mu, Yanhua Chen, He Li, Jingwen Sun, Baoxia Mu, Paolo Colombo
Ceramic cores are the key components of precision casting hollow turbine blades, and 3D‐printed silica‐based ceramic cores are crucial to the development of the aerospace industry. However, silica‐based ceramic cores have problems in terms of mechanical properties and friction properties. In this paper, silica ceramics were prepared by stereolithography‐based 3D printing technology and processed at different sintering temperatures. The effect of sintering temperature on the microstructure, physical–mechanical properties, and friction and wear properties of the silica ceramics was investigated. The results show that, with the increase of sintering temperature, the average particle size and bulk density of the samples increased, while the open porosity and layer thickness decreased. The surface of ceramics became more and more flat with the increase in temperature. The flexural strength first increased with increasing temperature, and then suddenly decreased at 1350°C. The average surface roughness decreased with increasing temperature. The wear of the material decreased with increasing sintering temperature and increased at 1350°C. The optimum sintering temperatures were 1250°C and 1300°C, giving a flexural strength of 23.18 and 23.25 MPa, bulk density of 1.72 and 1.78 g/cm3, and open porosity of 24.49% and 23.66%, respectively.
{"title":"Improved precision and mechanical properties of 3D‐printed silica ceramics via sintering temperature optimization","authors":"Yunsong Mu, Yanhua Chen, He Li, Jingwen Sun, Baoxia Mu, Paolo Colombo","doi":"10.1111/ijac.14880","DOIUrl":"https://doi.org/10.1111/ijac.14880","url":null,"abstract":"Ceramic cores are the key components of precision casting hollow turbine blades, and 3D‐printed silica‐based ceramic cores are crucial to the development of the aerospace industry. However, silica‐based ceramic cores have problems in terms of mechanical properties and friction properties. In this paper, silica ceramics were prepared by stereolithography‐based 3D printing technology and processed at different sintering temperatures. The effect of sintering temperature on the microstructure, physical–mechanical properties, and friction and wear properties of the silica ceramics was investigated. The results show that, with the increase of sintering temperature, the average particle size and bulk density of the samples increased, while the open porosity and layer thickness decreased. The surface of ceramics became more and more flat with the increase in temperature. The flexural strength first increased with increasing temperature, and then suddenly decreased at 1350°C. The average surface roughness decreased with increasing temperature. The wear of the material decreased with increasing sintering temperature and increased at 1350°C. The optimum sintering temperatures were 1250°C and 1300°C, giving a flexural strength of 23.18 and 23.25 MPa, bulk density of 1.72 and 1.78 g/cm<jats:sup>3</jats:sup>, and open porosity of 24.49% and 23.66%, respectively.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"23 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The mechanical, thermophysical, and ablation properties of 2.5D C/HfC–SiC composites with various SiC/HfC ratios are studied. The S7‐C/HfC–SiC composite with a high SiC/HfC volume ratio of 30.4/15.2 has the highest flexural strength of 203.4 ± 26.8 MPa and fracture toughness of 10.0 ± .5 MPa·m1/2. All C/HfC–SiC composites have a similar low thermal conductivity of ∼2 W·m−1·K−1 and their CTEs are in the range of .45–4.0 × 10−6/K from 30°C to 1400°C. S5‐C/HfC–SiC with medium SiC/HfC ratio possesses the lowest mass ablation rate of .29 ± .02 mg·cm−2·s−1 and linear ablation rate of .003 ± .0002 mm/s. The C/HfC–SiC composites are endowed with a pitting corrosion feature according to the morphology and composition evolution of the ablated surface, which results from both high temperature and stagnation pressure gradients in the radial direction of the oxyacetylene torch.
{"title":"Mechanical, thermophysical, and ablation properties of C/HfC–SiC composites with various SiC/HfC ratios","authors":"Chunlei Yan, Fangming Liu, Wei Wang, Rongjun Liu","doi":"10.1111/ijac.14878","DOIUrl":"https://doi.org/10.1111/ijac.14878","url":null,"abstract":"The mechanical, thermophysical, and ablation properties of 2.5D C/HfC–SiC composites with various SiC/HfC ratios are studied. The S7‐C/HfC–SiC composite with a high SiC/HfC volume ratio of 30.4/15.2 has the highest flexural strength of 203.4 ± 26.8 MPa and fracture toughness of 10.0 ± .5 MPa·m<jats:sup>1/2</jats:sup>. All C/HfC–SiC composites have a similar low thermal conductivity of ∼2 W·m<jats:sup>−1</jats:sup>·K<jats:sup>−1</jats:sup> and their CTEs are in the range of .45–4.0 × 10<jats:sup>−6</jats:sup>/K from 30°C to 1400°C. S5‐C/HfC–SiC with medium SiC/HfC ratio possesses the lowest mass ablation rate of .29 ± .02 mg·cm<jats:sup>−2</jats:sup>·s<jats:sup>−1</jats:sup> and linear ablation rate of .003 ± .0002 mm/s. The C/HfC–SiC composites are endowed with a pitting corrosion feature according to the morphology and composition evolution of the ablated surface, which results from both high temperature and stagnation pressure gradients in the radial direction of the oxyacetylene torch.","PeriodicalId":13903,"journal":{"name":"International Journal of Applied Ceramic Technology","volume":"12 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142180370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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