工业纯钛室温蠕变性能试验

Experimental Study on the Creep Performance of Titanium at Room Temperature

采用标准拉伸试验方法和小冲杆微试样试验技术测定钛材在室温下的蠕变性能,证实工业纯钛在室温下确实存在蠕变现象,但蠕变仅在应力足够大时发生。采用塑性薄膜伸张模型,将小冲杆试验测得的试样中心点挠度值δ转化为表征蠕变应变εSP和表征蠕变应力σSP,计算得到了与传统拉伸蠕变试验相应的蠕变应力-蠕变速率关系,比较结果说明两种测试方法获得的纯钛在室温下的蠕变速率较为接近。

Both the standard uniaxial tensile tests and the small punch tests were accomplished to study the creep behavior of TA2 at room temperature. The creep phenomenon of commercial purity titanium at room temperature is proved .Creep will occur only when the acting load is large enough. An expression of small punch specimen of certain size concerned with central deflection δ and characteristic creep strain ε_(SP)and characteristic creep stress σ_(SP) is deduced from a plastic membrane stretch model. Testing results of the small punch test can be converted to creep properties information successfully, which is compared with that from traditional standard uniaxial creep test with only small error.