MECHANISM OF CRACK NUCLEATION AND PROPAGATION OF FERRITE DUCTILE IRON DURING IMPACT FRACTURE UNDER LOW TEMPERATURES

IMR OpenIR

	MECHANISM OF CRACK NUCLEATION AND PROPAGATION OF FERRITE DUCTILE IRON DURING IMPACT FRACTURE UNDER LOW TEMPERATURES
其他题名	MECHANISM OF CRACK NUCLEATION AND PROPAGATION OF FERRITE DUCTILE IRON DURING IMPACT FRACTURE UNDER LOW TEMPERATURES
	Zhang Xinning; Qu Yingdong; Li Rongde; You Junhua
	2015
发表期刊	ACTA METALLURGICA SINICA
ISSN	0412-1961
卷号	51 期号:11 页码:1333-1340
摘要	Due to its excellent ductility and moderate strength, QT400-18L ferrite ductile iron has been widely used in producing core components of wind power equipment such as the hub of a wind turbine. Most of the researches have focused on the exploration of mechanical properties at low temperature, but none of them give the explanation on microcosmic mechanism of ductile iron during low temperature impact and the mechanism of crack nucleation and propagation of ferrite ductile iron during impact fracture has not been analyzed. In this work, the impact toughness of QT400-18L ferrite ductile iron was measured by V-notch Charpy impact test at different temperatures, the influence of low temperature impact toughness and the fracture behavior of ferrite ductile iron were discussed. The results show that the cleavage fracture resistance of QT400-18L ferrite ductile iron is reduced with the decrease of impact temperatures. Above ductile-brittle transition temperature (DBTT), most of the total fracture energies are expended during the crack propagation process. Below DBTT, both crack initiation energy and crack propagation energy decrease obviously. By using in situ fracture metallographic observation method, crack initiation and propagation of QT400-18L ferrite ductile iron under different temperatures were analyzed. Above DBTT, graphite nodules play the role of crack blunting and reducing crack propagation rate; in DBTT range, the fracture morphology shows mixed fracture with cleavage and dimples, which are related to graphite nodules; below DBTT, deformation twins lead to the nucleation of microcrack and result in cleavage fracture, the deformation twinning could possibly play a significant role in the ductile to brittle transition of QT400-18L ferrite ductile iron.
关键词	BRITTLE TRANSITION-TEMPERATURE STEELS graphite nodule ductile-brittle transition cleavage fracture deformation twin
收录类别	CSCD
语种	英语
资助项目	[National Natural Science Foundation of China] ; [Natural Science Foundation of Liaoning Province] ; [Program of Bureau of Shenyang Science and Technology]
CSCD记录号	CSCD:5562024
引用统计	被引频次：3[CSCD] [CSCD记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/143151
专题	中国科学院金属研究所
作者单位	中国科学院金属研究所
推荐引用方式 GB/T 7714	Zhang Xinning,Qu Yingdong,Li Rongde,et al. MECHANISM OF CRACK NUCLEATION AND PROPAGATION OF FERRITE DUCTILE IRON DURING IMPACT FRACTURE UNDER LOW TEMPERATURES[J]. ACTA METALLURGICA SINICA,2015,51(11):1333-1340.
APA	Zhang Xinning,Qu Yingdong,Li Rongde,&You Junhua.(2015).MECHANISM OF CRACK NUCLEATION AND PROPAGATION OF FERRITE DUCTILE IRON DURING IMPACT FRACTURE UNDER LOW TEMPERATURES.ACTA METALLURGICA SINICA,51(11),1333-1340.
MLA	Zhang Xinning,et al."MECHANISM OF CRACK NUCLEATION AND PROPAGATION OF FERRITE DUCTILE IRON DURING IMPACT FRACTURE UNDER LOW TEMPERATURES".ACTA METALLURGICA SINICA 51.11(2015):1333-1340.