Laves相对P92钢冲击韧性影响的试验研究  

Influence of Laves Phase on Impact Toughness of P92 Steel

作　　者：张红军[1] 周荣灿[1] 范长信[1] 

机构地区：[1]西安热工研究院有限公司,西安710032

出　　处：《动力工程学报》2012年第1期84-88,共5页Journal of Chinese Society of Power Engineering

摘　　要：对650℃时效500 h、1 000 h、3 000 h和10 000 h的P92钢以及时效后经过760℃回火处理的试样进行了冲击吸收能量、冲击断口和微观组织的试验,并定量分析了Laves相对P92钢冲击性能的影响程度.结果表明:冲击吸收能量、冲击断口的晶状断面率与组织中的Laves相含量之间的变化趋势一致,存在对应关系;Laves相对P92钢热脆化的影响程度取决于时效时间,在短时时效下,Laves相的析出和长大占主导地位,随着时效时间的增加,其影响份额逐渐降低,组织中的其他变化变得逐渐重要,但Laves相的析出和长大仍是主要影响因素;760℃回火可使Laves相发生回溶,并改善了冲击韧性,短期时效试样的冲击韧性可完全恢复到正、回火状态,但冲击吸收能量的组成比例却发生了变化.Experimental tests were conducted to study the impact absorbed energy,impact fracture appearance and the fracture microstructures of P92 samples aged at 650 ℃ respectively for 500 h,1 000 h,3 000 h and 10 000 h,and the samples tempered at 760 ℃ after aging treatment,while the influence of Laves phase on the impact property analyzed quantitatively.Results show that the impact absorbed energy and impact fracture appearance have a corresponding relationship with the Laves phase quantity in the sample.The degree of influence of Laves pahse on thermal embrittlement of P92 steel depends on the aging time.When the aging time is short,the precipitation and growth of Laves phase will play a dominant role in influencing the embrittlement.With the rise of aging time,the influence degree reduces gradually,however,the precipitation and growth of Laves phase will still play a role in this aspect.Re-dissolution of Laves phase occurs during tempering at 760 ℃,which may greatly improve the impact toughness and make it completely recovered to the normalized or tempered condition if the sample has been aged for a short duration;however,the fracture appearance mayhave some changes.

关 键 词：P92钢 LAVES相 冲击吸收能量 冲击韧性 回火处理 

分 类 号：TG115[金属学及工艺—物理冶金]