稀土学报(英文版)
稀土學報(英文版)
희토학보(영문판)
JOURNAL OF RARE EARTHS
2003年
3期
368-371
,共4页
关庆丰%方建儒%姜启川%王树奇
關慶豐%方建儒%薑啟川%王樹奇
관경봉%방건유%강계천%왕수기
metal materials%modification%cast hot-work die steel%thermal fatigue%rare earths
The effects of RE modification on structure and the properties of a new cast hot-work die (CHD) steel were investigated. The grains of the CHD steel are refined by RE modification. With the increase of RE addition, both grain size and inclusion amount are reduced. Appropriate amount of RE results in decrease in inclusion amount and formation of spheroidal inclusions uniformly-distributed in steel, so that the morphology and distribution of inclusions are improved. RE composite modification favors the formation of bainite, austenite and fine lath martensite with dense dislocation. When the residual RE content reaches 0.02%, no obvious changes in strength and hardness are found, while fracture toughness and threshold of fatigue crack growth are increased. The impact toughness, elongation and reduction of cross sectional area are increased by a factor of two, and thermal fatigue resistance is also improved.
