机械外文翻译文献翻译--影响工件表面质量的因素(编辑修改稿)

机械外文翻译文献翻译--影响工件表面质量的因素(编辑修改稿)内容摘要：

e will change. Grinding burns when a surface temperature of phase change to millers temperature above, metal surface microstructure occurred change, make the surface of the metal strength and hardness of the lower, and with residual stress produce appear even microscopic cracks, this phenomenon is called grinding burns. Improve grinding burns grinding heat caused by grinding way is the root of the burn, so improving grinding burns by two ways: one is as far as possible to reduce the generation of grinding heat。 2 it is improved cooling condition, make as far as possible the quantity of heat to produce less workplace. The correct choice grinding wheel reasonable choice of cutting dosages improved cooling conditions. Surface layer residual stress. Produce residual stress of reason: cutting in processing the metal layer and the surface when there were plastic deformation occurs, the surface of the metal to hematocrit increase。 Cutting processing, cutting area will have a lot of heat cutting produce。 Different analysis of metallographic organization has different density, also have different olume is necessarily affected by the change of connected the matrix of the metal bar, hence residual stress produce. The main work surface eventually process to the choice of methods. Choose the 机械专业中英文文献翻译 main parts work surface eventually process method, we must consider the main parts of the specific work surface working conditions and the possible damage to the form. In alternating load, the machine parts on the surface of the local micro cracks, because of tensile stress of action to make primary crack expanding, resulting in parts fracture. Improve parts from the view point of fatigue damage resistance, the final process should choose the surface in the surface produces residual stress processing method. In the machining process, tools on the squash and friction make metal materials happen plastic deformation, cause the original residue area of distortion or groove lines deepened, increases the surface roughness. When the medium or medium low cutting speed cutting plastic material, the surface before the sword in easy to form a high hardness of the devolop, it can take the place of the cutting tool, but state very unstable, the develop generation, grow up and fall off will seriously affect the machined surface roughness value. In addition, in cutting process due to the strong scraps and former knife friction role and tear phenomenon, but also in processing on the surface may produce scale thorn, make processing surface roughness increases. Grinding surface layer analysis of metallographic organization changes and grinding burns Mechanical processing produces in the process of heat cutting processing surface of workplace will make the rise of temperature of the violently, when the temperature more than the workplace material metallographic organization changes of the critical temperature, metallographic organization change will occur. In grinding processing, because most grits before cutting Angle is negative, grinding temperature is high, the quantity of heat of generation is much higher than cutting calories at, and grinding heat have 60 to 80% to the workplace, so very prone to the change of metallographic organization, makes the metal surface hardness and strength of decline, produce residual stress and even cause microcracks, this phenomenon is called grinding burns. Produce grinding burns, processing surface often appear yellow, brown, purple, green and burn color, this is grinding surface oxidation of high temperature in instantaneous film under color. Different burns color, shows that the surface of different levels by burns. Grinding hardened steel, workplace surface layer due to the role of the instantaneous heat, it may produce the following three metallographic organization changes: If grinding surface layer temperature not over phase transition temperature, but more than martensite transition temperature, then martensite will change to bee low hardness of tempering methods, and meanwhile body or body, this call tempering burns. If grinding surface layer temperature more than phase transition temperatures, the martensite transformation for austenitic, at this time without cutting fluids, the grinding surface hardness fell sharply, surface was annealing, this phenomenon is called annealing burns. When dry grinding is easy to produce this kind of phenomenon. If grinding surface layer temperature more th。