非标准金属拉伸试样及夹具的设计与制备

The Design and Preparation of Non-standard Tensile Sample and Grips

金属的拉伸性能既是评定金属材料的重要指标,又是机械制造和工程设计、选材的主要依据.该研究利用CAD软件设计和数控电火花线切割车床制备了适合金属材料工程专业课程实验教学、毕业设计实验和科研项目实验用的非标准拉伸夹具和试样,以解决标准试样加工制备困难和成本高的问题.所设计的非标准拉伸试样外形尺寸参考了标准拉伸试样,有效避免了试样由于局部应力集中发生破坏导致实验结果不准确的情况发生.制备得到的非标准拉伸试样夹具强度达到了实验设计要求,夹具在使用过程中没有发生屈服和变形,并且夹具和试样之间的配合精度达到了我国金属拉伸试验的标准.使用本研究制备的夹具和试样所测得的不锈钢样品性能与标准样品具有可比性,夹具和试样在教学和研究实验中具有实用性.

The tensile property is not only an important indicator for evaluating the metal material, but also a main parameter for machinery manufacturing, engineering design and material selecting. The standard tensile sample preparation is difficult and cost. That is why we design a non-standard tensile grips and tensile sample using the Auto Computer Aided Design software and prepare them using numerically controlled elet- rical spark linear cutting-machine in this study. The non-standard tensile grips and tensile sample we design are suitable for metal material engineering experiment teaching of professional courses, graduation design ex- periment and research projects. The non-standard tensile sample used the dimensions of the standard tensile samples for references. It can effectively avoid the breaking of sample due to local stress concentration which will affect the accuracy of experimental results. The sthrength of the non-standard tensile sample grips meets the design sthrength. It did not yield during use. Meanwhile, the fit precision between the tensile sample and grips meet the metal tensile test standard of our country. The test rusults of non-standard and standard stainless steel samples are comparable, which mean that it is practical in the teaching and research experi- ment.