锡及锡合金抗拉强度测定不确定度的评定

Evaluation of uncertainty on tensile strength determination of tin and tin alloys

针对现有的一些锡及锡合金材料进行抗拉强度测定,测定方法按照GB/T228.1-2010执行,并按照JJF1059.1-2012的要求进行不确定度的评定。在规定应变速率条件下,锡及锡合金的抗拉强度的不确定度主要包括重复性测量引入的不确定度、试样尺寸测量引入的不确定度、试验机测力系统示值误差引入的不确定度、计算机数据采集系统引入的不确定度、数值修约引入的不确定度和试验温度影响引入的不确定度。通过试验,发现对于锡及锡合金的抗拉强度,可考虑把修约值精确到0.1MPa,甚至更小,以降低因修约引入的不确定度的影响。另外,对于锡合金的拉伸试验,建议把试验温度控制在(23±2)℃。

For some tin and tin alloy,tensile strength determination according to GB/T228.1-2010 and evaluation of uncertainty according to JJF1059.1-2012.Under specified strain rate,uncertainty of tensile strength for tin and tin alloys mainly includes uncertainty introduced by repetitive measurement,uncertainty by sample size measurement,uncertainty by sample value error of test machine,uncertainty by computer data acquisition system,uncertainty by numerical revision and uncertainty by influence of test temperature.After test,it was found that for tensile strength of tin and tin alloy,revision value can be considered accurate to 0.1 MPa,or even less,to reduce impact of uncertainty by numerical revision.In addition,for tensile test of tin alloy,it is recommended to control test temperature to(23±2)℃.