Effect of Rare Earth Composite Modification on Microstructure and Properties of a New Cast Hot-Work Die Steel
来源期刊：JOURNAL OF RARE EARTHS2003年第3期
论文作者：王树奇 方建儒 姜启川 关庆丰
Key words：metal materials; modification; cast hot-work die steel; thermal fatigue; rare earths;
Abstract: 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.
王树奇1，方建儒1，姜启川1，关庆丰1
(1.Department of Materials Science and Engineering, Jilin University, Changchun 130025, China)
Abstract: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.
Key words:metal materials; modification; cast hot-work die steel; thermal fatigue; rare earths;
【全文内容正在添加中】
