摘要
从大量钛合金板材室温拉伸试验中发现,如果板材试样夹具使用不当,会造成拉伸曲线异常,直接影响试验结果。为此,按照GB/T228-2002室温拉伸试验方法,分别选用规格为3.0mm和1.2mm厚的TA15以及2.5mm厚的TC4钛合金板材试样,采用打孔夹具和楔形夹具夹持试样进行室温拉伸试验,对拉伸曲线出现的异常现象进行了分析。结果表明,用打孔夹具夹持强度高达1000MPa的TA15,TC4板材试样进行拉伸试验时,将会发生连接销和试样孔接触打火、震动,孔变形而造成拉伸曲线出现异常驼峰现象,因此无法根据拉伸曲线计算出正确的屈服强度(σ0.2)。如果换用楔形夹具夹持试样进行试验,则可得到正常的拉伸曲线而不影响真实屈服强度的计算。故合理选取夹具进行试验,是获得正常拉伸曲线及真实强度值的关键因素。
During tensile test, the construction of sample clamp may directly affect the test result in which the tension curve truns to strange. Taking into account test method GB/T228-2002, the tnesile test was performed using TC4 plate of 2.5 mm and TA15 of 1.2, 3.0 mm in thickness as the test sample with the perforated and wedge clamp, and the strange phenomena of tension curves were analyzed. Te results show that when the perfolated clamp was used for holding TA15, TC4 sheet sample which is of 1 000 MPa, strength, it will be impossible to obtain correct σ0.1 data due to the shake, strike fire, and deformation of the sample, by which it caused camelback trend for the tangential path in front of yield point, and the curve flicking with the instantaneous drop of test force; when the wedge clamp was used for holding this kind of samples, the continuous tension curve in normal trend and smooth will be obtained. So selecting clamps correctly is the key to avoid disturbance during tensile test.
出处
《稀有金属快报》
CSCD
2006年第9期36-39,共4页
Rare Metals Letters
关键词
钛板
室温拉伸
夹具
拉伸曲线
titanium plate
tensile test at room temperature
clamp
tensile curve
