摘要
研究了微量稀土对Cr21Ni11N奥氏体耐热不锈钢高温热塑性及高温持久性能的影响。结果表明：在750~1250℃范围内,稀土显著提高耐热钢的热塑性,消除800℃的塑性低凹区,扩宽安全热加工温度范围近75℃。稀土显著延长耐热钢的高温持久寿命约3~5倍,并提高持久断裂塑性。钢中添加稀土后,其蠕变断裂机制由楔形裂纹为主的机制逐渐转变为空洞裂纹为主的机制,高温持久断口附近的楔形裂纹明显减少,且断口呈典型的韧窝状塑性断口特征。
The effect of minor RE addition on hot ductility and creep rupture properties of austenitic heat-resistant stainless steel Cr21Ni11N were investigated.The experimental results showed that the hot ductility of the alloy in the range of 750~1250 ℃ was improved significantly,and the ductility drop at 800 ℃ was eliminated.And also the safe temperature for hot working was extended nearly 75 ℃ by adding RE elements in this steel.Moreover,the creep rupture lives of the tested steels were extended considerably about 3~5 times,and the creep rupture ductility was increased.After adding minor RE,the creep mechanism was changed gradually from wedge crack to creep voids,the wedge cracks were reduced significantly near fracture surface,and the fracture morphology was classical characteristics of dimple fracture.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2009年第6期829-833,共5页
Journal of the Chinese Society of Rare Earths
基金
钢铁研究总院-宝钢集团战略合作资助项目(JK2008-020)
关键词
热塑性
高温持久
楔形裂纹
空洞裂纹
稀土
Hot ductility
creep rupture
wedge crack
void crack
rare earths
