机械产品在设计过程中,为了确保整机性能参数,经过必要的验算和综合分析后,针对不同工况条件的零件,选用与其相适应的材质;规定热处理和表面处理的要求,以通过机加工、热处理和表面处理,来达到零件应具有的尺寸与形位精度及所需的机械性能和物理特性。这就涉及冷、热、表三者在整个工艺中协调与统一。一、在机加工艺中对预先热处理的考虑就热处理而言,通常是根据图面规定,酌情留出加工余量,注意加工基准,编入适当工序中去就可实现。但是,对有些材质的零件则不然,要根据其材质 Mechanical products in the design process, in order to ensure that the performance parameters of the machine, after the necessary checking and comprehensive analysis, for different conditions of the parts, select the appropriate material; provisions of heat treatment and surface treatment requirements, through machining , Heat treatment and surface treatment, to achieve parts should have the size and shape accuracy and the required mechanical properties and physical properties. This involves cold, heat, table three in the entire process of coordination and unity. First, in the art of mechanical processing considerations on the pre-heat treatment For heat treatment is usually based on the provisions of the map, as appropriate, set aside the allowance, pay attention to the processing base, into the appropriate process can be achieved. However, some of the material parts are not, according to their material