In-situ observation of microstructural evolution in reheated low carbon bainite weld metals with various Ni contents

被引：0

作者：

Gao-jun Mao ^{[1
,2
]}

Rui Cao ^{[1
,2
]}

Jian-hong Chen ^{[1
,2
]}

Xi-li Guo ^{[3
]}

Yong Jiang ^{[3
]}

机构：

[1] Department of Materials Science and Engineering,Lanzhou University of Technology

[2] State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals,Lanzhou University of Technology

[3] Atlantic China Welding Concumables,Inc.

来源：

Journal of Iron and Steel Research(International) | 2017年 / 24卷 / 12期

基金：

中国国家自然科学基金;

关键词：

Weld metal; Ni content; Bainite; Nucleation site; Growth; In-situ observation;

D O I：

暂无

中图分类号：

TG142.1 [钢的组织与性能];

学科分类号：

080502 ;

摘要：

Microstructural evolution in weld metals was in-situ observed through utilizing a laser scanning confocal microscope at two cooling rates.The specimens with various nickel contents were adopted for the observation.In the specimen with low fraction of Ni(≤2 wt.%),granular bainite microstructure(i.e.broad surface relief)transformation from intragranular nucleation site was in-situ observed,while,lath bainite microstructure originating from grain boundary of austenite was in-situ observed for specimens with high mass percentage of Ni(≥4 wt.%).With increasing nickel content,the transformation temperature dropped.The prior austenite grain size was initially depressed and subsequently coarsened dramatically with the addition of Ni.The microstructure difference was ascribed to various nucleation sites and growth direction in the matrix.On account of those observations,not only the chemical component,cooling rate and microstructure were systematically correlated,but also the microstructural evolution was definite.

引用

页码：1206 / 1214

页数：9