作　　者： ; ; ; ;

机构地区： 东北大学材料与治金学院材料各向异性与织构工程教育部重点实验室

出　　处： 《稀有金属材料与工程》 2008年第1期66-71,共6页

摘　　要： 研究了电场处理后的长期时效GH4199合金在不同应变速率下的拉伸变形行为。结果表明,随应变速率增加合金屈服强度升高,应变速率低于3.3×100s-1时,应变速率敏感指数m值较低且随应变速率的增加无明显变化;当应变速率超过3.3×100s-1时,m显著升高,当应变速率为3.3×101s-1时,m达到0.16;随应变速率增加合金拉伸塑性呈下降趋势;在较低应变速率范围内变形时,电场处理后产生的退火孪晶是改善合金塑性的主要因素,随着应变速率的提高,晶内开动的滑移系数量增加,塑性变形能力随之提高,但存在于合金晶界处的连续分布的碳化物对晶界的弱化作用逐渐显露,晶界与晶内塑性变形能力差异增大,晶界成为断裂的主要途径,导致合金塑性降低。 The tensile deformation behavior of long-term aging GH4199 alloy after electrical field treatment under different strain rate was investigated. The results showed that the yield strength of the alloy increased with the increase of the strain rate. When the strain rate was lower than 3.3× 10^0 s^-1, the strain rate sensitivity coefficient m kept lower and had no obvious change with the increase of the strain rate. And when the strain rate was higher than 3.3 × 10^0 s^-1, the value of m increased greatly. When the strain rate was 3.3 × 10^1s^-1, the value of m was up to 0.16. The tensile plasticity decreased with the increase of the strain rate. During the deformation at lower strain rate, the annealing twins occurred during the electrical field treatment were the main factor to improve the plasticity of the alloy. With the increase of the strain rate, the plasticity of the alloy increased due to increasing the number of the activated slip systems inside the grains, while, the carbides aggregated continuously on the grain boundary weakened the plasticity of the grain boundary gradually and the difference of the plasticity between the grain boundary and inside the grain increased. Thus the grain boundary was the main way to rupture.

关 键 词： 应变速率 电场处理 高温合金 退火孪晶 变形行为

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺] [金属学及工艺] [一般工业技术] [金属学及工艺]