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Method of arc activation of the base at increasing the distance plasma spraying 增加等离子喷涂距离的电弧激活方法
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-9
A. Ershov, О. Zelenina
Purpose. To increase the efficiency of the plasma coating by developing a method of ion-arc activation of the base using an activating electrode, which leads to an increase in the adhesion strength of the coating due to the sputtering of surface oxides of the base. Research methods. Experimental and computational, mechanical tests, optical microscopy. The development of the method of ion-arc activation of the part base with an increase in the distance of coating deposition consists in application of an activating electrode located at the surface of the base to create an additional activating arc. The influence of the activating arc on bases for creating an additional activating arc. The influence of the activating arc on the adhesion strength of the coating is determined. The estimation of the current density of the activating arc for the sputtering of surface base oxides is carried out. Results. A method of arc activation of the base surface with an increase in the coating distance is found. It is shown that application of an activating arc of reverse polarity that burns between the additional electrode and the base leads to ion bombardment of the surface by sputtering surface oxides and the creation of microcraters on the base surface. As a result, the bond strength is doubled compared to the bond strength obtained without the use of ion-arc activation of the base. The calculations of the rate of cathodic sputtering of the surface oxides of the base are carried out and the minimum activation current density of the base is determined, which leads to the complete sputtering of a layer of oxides of a given thickness. Scientific novelty. It has been determined that, despite the rapid oxidation of the base under atmospheric conditions, application of the method of ion-arc cleaning of the surface during coating leads to a significant increase in the adhesion strength of the coating to the base. Practical value. The obtained results of increasing the adhesion strength rise the efficiency, the guaranteed service life of the plasma coating on the parts of machines and mechanisms
目的。为了提高等离子体涂层的效率,开发了一种使用激活电极对基底进行离子弧活化的方法,该方法由于基底表面氧化物的溅射而导致涂层的附着力增加。研究方法。实验和计算,机械测试,光学显微镜。随着涂层沉积距离的增加,离子弧激活零件底座的方法的发展包括在底座表面应用激活电极以产生额外的激活电弧。激活电弧对产生附加激活电弧的基底的影响。测定了活化电弧对镀层附着力的影响。对表面基氧化物溅射激活电弧的电流密度进行了估计。结果。提出了一种随着涂层距离的增加而使基面电弧活化的方法。结果表明,在附加电极和基体之间燃烧的反极性激活电弧的应用会导致离子轰击表面,从而溅射表面氧化物并在基体表面产生微孔。结果,与不使用离子弧活化碱的结合强度相比,结合强度增加了一倍。计算了基底表面氧化物的阴极溅射速率,确定了基底的最小激活电流密度,从而使给定厚度的氧化层完全溅射。科学的新奇。已经确定,尽管在大气条件下基体会迅速氧化,但在涂层过程中应用离子弧清洗表面的方法可以显著提高涂层与基体的附着力。实用价值。结果表明,等离子体涂层的结合强度提高了效率,保证了机械和机构零件的使用寿命
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引用次数: 0
The problem of formation and ergonomics of ecologically compact electric transport 生态紧凑型电动交通的形成与人机工程学问题
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-14
V. Kardashov, О. Kashuba
The problem of formation and ergonomics of ecologically compact electric transport
生态紧凑型电动交通的形成与人机工程学问题
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引用次数: 0
Quality evaluation of metal surfaces treatment by wavelet analysis 基于小波分析的金属表面处理质量评价
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-10
L. Deineha, А. Berezhnoi, V. Kozlov, V. Sudakov
Purpose. Analyze the effectiveness of using wavelet analysis to assess the quality of metal surfaces. Investigate the possibility of using wavelet analysis in ultrasonic flaw detection. Determine the optimal wavelet families and their criteria for assessing the quality of metal surface processing. Research methods. Orthogonal wavelets are considered: Daubechies wavelet, Simlet wavelet and Coiflet wavelet, which provide the possibility of performing a discrete wavelet transform procedure. The criteria influencing the effectiveness of ultrasonic signal filtering by methods using wavelet analysis are considered. Ultrasonic signals were filtered using wavelet functions. Results. It has been determined that for successful signal filtering, the selected wavelet method must provide a discrete wavelet transformation and have a similarity in the wavelet function shape in the local features of the ultrasonic signals flaw detector. During the work, a rigid threshold for limiting the detail coefficients of wavelet analysis was chosen, as it is the best for filtering tasks. The filtering efficiency is confirmed by the relatively high signal to noise ratio, as well as by the fact that the shape of the pulse extracted from the defect remained almost unchanged. Scientific novelty.  When using the Daubechies and Coiflet wavelets as basic functions, as a result of wavelet filtering, it was possible to increase the signal to noise ratio by 20 dB and confidently isolate the useful signal against the background noise, which indicates the prospects of using this kind of transformations in filtering problems. Practical value. The obtained solutions can be used for implementation in signal filtering algorithms in digital processing units of automated non-destructive ultrasonic control systems.
目的。分析了小波分析在金属表面质量评价中的有效性。探讨小波分析在超声探伤中的应用可能性。确定最优小波族及其评价金属表面加工质量的标准。研究方法。考虑正交小波:Daubechies小波,Simlet小波和Coiflet小波,它们提供了执行离散小波变换过程的可能性。考虑了影响小波分析方法对超声信号滤波效果的判据。利用小波函数对超声信号进行滤波。结果。确定了要使信号滤波成功,所选择的小波方法必须提供离散小波变换,并且在超声探伤信号的局部特征中具有相似的小波函数形状。在工作中,选择了一个严格的阈值来限制小波分析的细节系数,因为它最适合滤波任务。相对较高的信噪比以及从缺陷中提取的脉冲形状几乎保持不变的事实证实了滤波效率。科学的新奇。当使用Daubechies和Coiflet小波作为基本函数时,由于小波滤波,可以将信噪比提高20 dB,并且可以自信地将有用信号从背景噪声中分离出来,这表明了在滤波问题中使用此类变换的前景。实用价值。所得到的解可用于实现自动无损超声控制系统数字处理单元的信号滤波算法。
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引用次数: 0
Model of the impurities redistribution in the surface layer of an alloy under the action of pulsed laser radiation 脉冲激光作用下合金表层杂质重分布的模型
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-15
I. Titov, А. Nedolya
Model of the impurities redistribution in the surface layer of an alloy under the action of pulsed laser radiation
脉冲激光作用下合金表层杂质重分布的模型
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引用次数: 0
Stress-deformed state of the shell with a small initial deflection under the action of the end load 壳体在端载作用下初始挠度较小的应力变形状态
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-11
I. Pozhueva, Т. Levitskaya
Purpose of work. Construction of method for calculating the stress-strain state of cylindrical shell with small initial deflection, to which an end load is applied, using the method of characteristics. Comparison of the calculation results of the obtained model with the works of other authors in this area. Research methods. For the calculation, the equations of motion of the Timoshenko type shell were used, taking into account both the shear deformation and inertia of rotation, and some nonlinear terms, to which the method of characteristics was applied. To obtain the equations of shell motion, the Hamilton-Ostrogradsky variational principle was used. Results method is proposed for calculating the stress-strain state of a cylindrical shell with a small initial deflection using characteristics. Comparative analysis of the calculation results with research in this area by other authors, which showed the effectiveness of the proposed method. Scientific novelty. The equations of the classical theory of shells, based on the Kirchhoff-Love hypotheses, which do not take into account the shear deformation and inertia of rotation, as well as linear equations of the Timoshenko type, have become widespread. In this work, a model of the stress-strain state of an axisymmetric shell with small initial deflections is constructed, taking into account both shear deformation and rotational inertia, and some nonlinear terms. Practical value. The proposed method can be used to calculate the stress-strain state of structures in which thin shells are present as elements, taking into account small initial deflection. This method makes it possible to study the influence of the characteristics of the initial deflection on the stress-strain state of the entire structure.
工作目的。建立了端载作用下小初始挠度圆柱壳应力-应变状态的特征值法计算方法。将所得模型的计算结果与该领域其他作者的著作进行了比较。研究方法。在计算中,采用了考虑剪切变形和转动惯量的Timoshenko型壳的运动方程和一些非线性项,并对其采用特征化方法。利用Hamilton-Ostrogradsky变分原理得到壳层运动方程。结果提出了利用特性计算小初始挠度圆柱壳应力-应变状态的方法。将计算结果与其他作者在该领域的研究结果进行了对比分析,表明了所提方法的有效性。科学的新奇。基于Kirchhoff-Love假设的经典壳理论方程,不考虑剪切变形和旋转惯性,以及Timoshenko类型的线性方程,已经得到广泛应用。本文建立了考虑剪切变形、转动惯量和一些非线性项的小初始挠度轴对称壳的应力-应变状态模型。实用价值。所提出的方法可用于计算以薄壳为单元的结构的应力-应变状态,并考虑小的初始挠度。该方法使研究初始挠度特性对整个结构应力应变状态的影响成为可能。
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引用次数: 0
Professional direction of physics teaching of future engineers: practical aspect 未来工程师物理教学的专业方向:实践性方面
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-16
L. Gulyaeva
Professional direction of physics teaching of future engineers: practical aspect
未来工程师物理教学的专业方向:实践性方面
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引用次数: 0
Design of a beam of variable cross-section on the elastic base by the quasi-analytical method considering boundary conditions 考虑边界条件的弹性基底变截面梁的拟解析设计
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-12
Р. Shtanko, S. Ryagin, І. Geletiy, А. Kononenko
Purpose. Improvement of the quasi-analytical method of nonlinear differential equation solution and its approbation with reference to beams of variable cross-section on the elastic base with two base factors. Research methods. Boundary conditions in the form of required number of correspondently transformed equations are added to the system of the linear algebraic equations which results from substitution of approximating function with constant factors (for example – power function) in the nonlinear differential equation and fixation of a set of variable values. The total number of the equations have to correspond to quantity of constant factors if the further solution will be carried out by an analytical method. Results. Deflection diagram of a trapezoid concrete beam with rectangular cross-section of variable height on the elastic base with two base factors has been calculated during approbation. Average solution error was equal to 0.06%. Distributions of the bending moments and normal stresses along the beam have been researched. Scientific novelty. The authors did not meet in literature such method of nonlinear differential equation solution. Practical value. The quasi-analytical method with realised consideration of boundary conditions that has been offered can be used for solution of differential equations of any order with various types of nonlinearity, including calculations of beams of variable cross-section on the elastic base.
目的。双基因素弹性基上变截面梁非线性微分方程拟解析解的改进及其认可。研究方法。在非线性微分方程中,用常因子(如幂函数)代替近似函数,固定一组变量值,从而得到线性代数方程组,在方程组中加入所需数量的相应变换方程形式的边界条件。如果用解析法进一步求解,则方程的总数必须与常数因子的数量相对应。结果。在审核过程中,计算了弹性基础上具有两个基础因素的变高度矩形截面梯形混凝土梁的挠度图。平均溶液误差为0.06%。研究了弯矩和正应力沿梁的分布。科学的新奇。作者在文献中没有遇到这种非线性微分方程解的方法。实用价值。所提出的考虑边界条件的拟解析方法可用于求解各种非线性的任意阶微分方程,包括弹性基础上变截面梁的计算。
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引用次数: 0
Obtaining tube blanks from copper-nickel alloy МНЖ 5-1 when using a tool made of die steel adjustable austenitic transformation during operation 使用模具钢制作的工具获得铜镍合金МНЖ - 5-1管坯,在操作过程中可调节奥氏体相变
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-4
O. Sydorchuk
Purpose. Production of die tool from steel with regulation of austenitic transformation during operation to increase the level of service life during hot deformation of copper-nickel alloy. Research methods. Metallographic, high-temperature X-ray phase and dilatometric analyzes of research steel. Results. The mode of heat treatment (incomplete annealing) of steel 4Х3Н5М3Ф at a temperature of 750±20 °С, obtained by electroslag remelting, allowed to obtain a perlite-sorbitol structure at a hardness of33–34 HRC and allowed better machining by cutting the workpiece alloy. The proposed mode of final heat treatment (hardening 1030±10 °C and tempering 600±5 °C) of the investigated steel, makes it possible to heat the matrix during operation to a temperature of 600 °C. Scientific novelty. The thermal stability of the tool for hot deformation can be significantly increased when using steel with adjustable austenitic transformation during operation. Such steel in the initial state has a ferrite base, and when heated to operating temperatures occurs from α-Fe to γ-Fe conversion and, subsequently, the austenitic structure is preserved throughout the period of high-temperature operation of the stamping tool. It is confirmed that the stamping tool made of steel 4Kh3N5М3F when pressing a copper-nickel alloy works in the temperature range corresponding to the austenitization process. Practical value. Abbreviated technological operation, namely thermo-deformation processing (forging) of ingots obtained by electroslag remelting. Experimental-industrial tests of the die tool of steel 4Х3Н5М3Ф in the manufacture of tube blanks of Ø 67±0,1 mm from a copper-nickel alloy of the МНЖ 5-1 brand are carried out. As a result of research “Artemovsk plant for processing of non-ferrous metals and alloys” (Bakhmut, Donetsk region, Ukraine) at an operating temperature of 900–950 ° C, matrices made of steel 4Х3Н5М3Ф (without deformation-forging) showed stability in three times higher than the matrices from steel 3Х3М3Ф made at the enterprise.
目的。在使用过程中调节奥氏体相变的钢生产模具,提高铜镍合金热变形的使用寿命水平。研究方法。研究钢的金相、高温x射线相及膨胀分析。结果。通过电渣重熔获得的钢材4Х3Н5М3Ф在750±20°С的温度下的热处理(不完全退火)方式,可以获得硬度为33 - 34 HRC的珍珠岩-山梨醇结构,并且可以通过切削工件合金进行更好的加工。所研究钢的最终热处理模式(硬化1030±10°C,回火600±5°C)使得在操作过程中将基体加热到600°C的温度成为可能。科学的新奇。使用可调节奥氏体相变的钢,可显著提高热变形刀具的热稳定性。这种钢在初始状态下具有铁素体基体,当加热到工作温度时,发生从α-Fe到γ-Fe的转换,随后在整个冲压工具高温工作期间保持奥氏体组织。证实了用钢材4Kh3N5М3F制成的冲压工具在压制铜镍合金时,工作在与奥氏体化过程相对应的温度范围内。实用价值。简称工艺操作,即对电渣重熔得到的钢锭进行热变形加工(锻造)。对4Х3Н5М3Ф钢模具在МНЖ -1牌号铜镍合金Ø 67±0.1 mm管坯生产中的应用进行了工业性试验。根据“阿尔特莫夫斯克有色金属和合金加工工厂”(乌克兰顿涅茨克地区巴克穆特)在900-950°C工作温度下的研究结果,由钢铁4Х3Н5М3Ф(不变形锻造)制成的基体的稳定性比该企业制造的钢铁3Х3М3Ф基体高三倍。
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引用次数: 0
Features of the process of hot extrusion of blanks of the rotor blades of a GTE compressor 介绍了GTE压缩机转子叶片毛坯热挤压工艺特点
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-7
O. Kachan, S. Ulanov
Purpose. Improving the quality of manufacturing of blanks for compressor rotor blades by hot extrusion. Research methods and equipment. The research was carried out using a crank press with a force of 1000 kN, in split dies in accordance with a serial technological process. The dies were heated up to 150 ... 200 °С, to improve the work when extruding the blanks of the rotor blades made from the titanium alloy ВT8. The thickness of the copper coating was measured with an ИTMП-3 magnetic induction device with an error of ± 2 μm. X-ray spectral microanalysis was performed on an ISM-6360ALA scanning microscope. The billets were heated in an MП-2В furnace. Results. It has been established that the quality of blade blanks made of ВT8 titanium alloy obtained by hot extrusion is influenced by the state of the copper coating, which is preliminarily applied to the surface of the original blank. When the initial blanks are heated, copper is oxidized and in the temperature range of 250…700 °С the oxidation rate proceeds according to a linear pattern, and after 700…750 °С – according to a parabolic pattern. Oxidation of the copper coating occurs unevenly not only within one workpiece, but also within the batch, which leads to a decrease in durability and deterioration of the surface quality of the blade workpieces obtained by hot extrusion. Research carried out by X-ray spectral microanalysis of the copper coating revealed the presence of aluminum oxides of varying degrees of dispersion. The source of this material in the copper coating is caricature of corundum used in blowing into the surface of the billet, which is the reason for the appearance of scoring on the blade blank. It was also found that longitudinal marks on the blade are a consequence of the appearance of a matrix of tubercles (sagging) on the working surface of the die, caused by the adhesion of the deformable material of the blade to the base metal of the tool. Scientific novelty. The regularity of the influence of the heating temperature of the initial blank of the blade on the oxidation rate of the copper coating has been established. The mechanism of the influence of the oxidation of the copper coating and the adhesion of contacting materials during hot extrusion on the surface condition of the resulting blanks is disclosed. Practical value. The results obtained make it possible to improve the quality of the manufactured blanks of the compressor rotor blades by hot extrusion.
目的。提高压气机转子叶片热挤压毛坯的生产质量。研究方法和设备。研究是在一个压力为1000千牛的曲柄压力机上,按照一系列的工艺流程在分模中进行的。模具被加热到150度。200°С,提高钛合金转子叶片毛坯挤压时的工作效率ВT8。采用ИTMП-3磁感应仪测量铜镀层厚度,测量误差为±2 μm。在ISM-6360ALA扫描显微镜上进行x射线光谱显微分析。钢坯在MП-2В炉中加热。结果。初步确定了在原毛坯表面涂覆铜层的状态对ВT8钛合金热挤压叶片毛坯质量的影响。当最初的毛坯被加热时,铜被氧化,在250…700°С的温度范围内,氧化速率按线性模式进行,在700…750°С之后-按抛物线模式进行。铜镀层的氧化不仅在一个工件内发生不均匀,而且在批量内也会发生不均匀氧化,导致热挤压叶片工件的耐用性下降,表面质量恶化。通过对铜涂层进行x射线光谱微分析,发现存在不同程度分散的氧化铝。铜涂层中这种物质的来源是吹入钢坯表面时使用的刚玉的图案,这是导致叶片毛坯出现划痕的原因。还发现,刀片上的纵向痕迹是由于刀片的可变形材料粘附在刀具的母材上,在模具的工作表面上出现了结节(下垂)基质的结果。科学的新奇。建立了叶片初始毛坯加热温度对铜涂层氧化速率的影响规律。公开了热挤压过程中铜涂层的氧化和接触材料的粘附对所得毛坯表面状况的影响机理。实用价值。研究结果为提高压气机转子叶片热挤压坯料质量提供了可能。
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引用次数: 0
Increasing of the steels properties by an ecological method of isothermal and step quenching 采用等温阶梯淬火生态法提高钢的性能
Pub Date : 2021-09-14 DOI: 10.15588/1607-6885-2021-2-5
L. Malinov, V. Malinov, D. Burova
The relevance. Improving the mechanical properties of steels makes it possible to increase the service life of machine parts, which is an important task in materials science. One of the promising directions in its solution is to obtain in steel a multiphase structure, one of the main components of which is metastable austenite, which undergoes a dynamic deformation martensitic transformation (DDMT) - self-hardening effect under loading (SHL). Methods providing the required structure are isothermal and step quenching. However, at present, when they are carried out for cooling from the austenitizing temperature and holding at the constant temperature used non-environmentally friendly substances: heated oil, molten salts or alkalis. In this regard the actual problem is the exclusion of them from the technological process. The possibility of solving this problem on several steels has shown. Purpose is to show the possibility of increasing the mechanical properties of the studied steels 30ХГСА, 38ХС, 45Г, 40ХН, 10Г12, 60Х18 by using rational modes of an environmentally friendly method of steels quenching (isothermal - for low-alloyed and step - for high-alloyed) due to obtaining in their structure along with other components of metastable residual austenite and the implementation of the SHL effect. Research methods. Samples of the investigated steels after austenitization (in some cases with holding in IСIT) were cooled in water to the temperature of lower bainite formation (isothermal quenching) or stabilization of supercooled austenite to martensitic transformation upon cooling (step quenching), after which they were kept in a furnace and cooled in air to room temperature. Durometric, metallographic and X-ray research methods were used. The tensile properties and impact strength were determined. These properties were compared with those obtained for the studied steels after a typical heat treatment, including quenching in oil and tempering. Results. It is shown that isothermal and step quenching of the investigated steels without the use of non-environmentally friendly substances, carried out according to rational modes, makes it possible to increase the mechanical properties in comparison with their level after the commonly used quenching in oil (fire hazard, the vapors are cancerogenic) and tempering. This is achieved by obtaining a multiphase structure with metastable austenite. Scientific novelty. It is proposed to obtain a multiphase structure with metastable austenite in them to improve the mechanical properties of the studied steels by conducting isothermal and step quenching in an environmentally friendly way without using heated oil, molten salts or alkalis. Practical value. For the studied steels the modes of isothermal and step quenching are determined in an environmentally friendly way, which make it possible to increase the mechanical properties in comparison with the level achieved by quenching and tempering. Wherein in contrast t
的相关性。提高钢的力学性能,使机械零件的使用寿命得以延长,是材料科学的重要课题。在钢中获得以亚稳奥氏体为主要成分之一的多相组织,发生动态变形马氏体相变(DDMT) -加载自硬化效应(SHL)是解决这一问题的一个有希望的方向。提供所需结构的方法是等温淬火和阶梯淬火。然而,目前,当它们从奥氏体化温度进行冷却和恒温保温时,使用的是非环保物质:加热油、熔盐或碱。在这方面,实际问题是将它们排除在技术过程之外。在几种钢上解决这个问题的可能性已经显示出来。目的是显示通过使用合理的环境友好钢淬火方法(等温-低合金和阶梯-高合金)的方式来提高所研究钢30ХГСА, 38ХС, 45Г, 40ХН, 10Г12, 60Х18的机械性能的可能性,因为在其结构中获得了亚稳残余奥氏体的其他成分,并实现了SHL效应。研究方法。在奥氏体化(在某些情况下,在IСIT中保温)后,将所研究的钢样品在水中冷却到下贝氏体形成的温度(等温淬火)或冷却时过冷奥氏体到马氏体转变的稳定温度(阶梯淬火),之后将其保存在炉中并在空气中冷却到室温。采用了硬度学、金相学和x射线研究方法。测定了材料的拉伸性能和冲击强度。这些性能与经过典型热处理(包括油淬和回火)后得到的性能进行了比较。结果。结果表明,在不使用非环保物质的情况下,按照合理的方式对所研究的钢进行等温和阶梯淬火,与常用的油淬(有火灾危险,蒸汽致癌)和回火相比,可以提高钢的力学性能。这是通过获得具有亚稳奥氏体的多相结构来实现的。科学的新奇。建议在不使用加热油、熔盐或碱的情况下,采用环境友好的等温和阶梯淬火方法,获得含有亚稳奥氏体的多相结构,以改善所研究钢的力学性能。实用价值。对于所研究的钢,以一种环保的方式确定了等温和阶梯淬火的模式,这使得与淬火和回火所达到的水平相比,有可能提高机械性能。其中,与类似的典型淬火方法相比,不包括购买盐或碱、处理它们以及从中洗涤产品的成本。与淬火回火相比,新方法不需要使用油和回火。后者改善了生态环境,减少了热处理过程中的能耗。
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引用次数: 0
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Innovative Materials and Technologies in Metallurgy and Mechanical Engineering
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