Effect of sub-zero cooling on microstructure and mechanical properties of a low alloyed austempered ductile iron

被引：0

作者：

S. Yazdani

M. Ardestani

机构：

[1] IRAN

[2] Faculty of Materials Engineering Sahand University of Technology

[3] Tabriz

来源：

China Foundry | 2007年 / 02期

关键词：

austempered ductile iron; austenite; sub-zero cooling; martensitic transformation; ausferrite;

D O I：

暂无

中图分类号：

TG143.4 [韧性铸铁（可锻铸铁）]; TG113 [金相学（金属的组织与性能）];

学科分类号：

080502 ;

摘要：

The effect of sub-zero cooling on microstructure and mechanical properties of a low alloyed austempered ductile iron has been investigated. Austempering of samples was performed at 325℃and 400℃after austenitizing at 875℃and 950℃. The sub-zero treatments were carried out by cooling down the samples to -30℃, -70℃and -196℃. The changes in volume fraction of austenite and mechanical properties were determined after cooling to each temperature. The austenite volume fraction of samples which were austenitized at 875℃and austempered at 325℃remained unchanged, whilst it reduced in samples austenitized at 950℃and 875℃for austempering temperature of 400℃. In these specimens, some austenite transformed to martensite after subzero cooling. Mechanical property measurements showed a slight increase in strength and hardness and decrease in elongation and toughness due to this transformation behavior.

引用

页码：120 / 123

页数：4

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[4]

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