极寒地带超韧性推土机刀片耐磨钢NM450E关键技术研发及应用

R&D and Application of Key Technology of Steel NM450E for Ultra-ductile Bulldozer Blade in Extremely Cold Zone

采用采用Nb+V+Ti+Cr+Mo化学成分体系,通过控制原始形变晶粒度、合金元素碳氮化物反复析出和再形核,获得极寒地带超韧性推土机刀片耐磨钢NM450E,抗拉强度1300~1450 MPa,延伸率A50≥12,布氏硬度430~470 HBW,-40℃低温冲击韧性57~150 J,良好的低温韧性可以满足在极寒地带、恶劣环境下进行服役,解决了工程机械以推土机为代表的刀板、刀片等产品的低温脆性断裂难题,而且工程机械产品整机重量减重17~40,使用寿命提高3~4倍。

The ultra ductile bulldozer blade wear-resistant steel NM450E applicable in extremely cold zone is obtained with tensile strength of 1300~1450 MPa,elongation ofA50≥12,Brinell hardness of 430-470HBW and low-temperature impact toughness of 57~150 J at-40℃,by using the Nb+V+Ti+Cr+Mo chemical composition system,by controlling the original deformation grain size,repeated precipitation and renucleation of alloy element carbonitride.The good low-temperature toughness can meet the service in extremely cold zone and harsh environment.It solves the problem of low-temperature brittle fracture of blades and other products of construction machinery represented by bulldozer.Moreover,the overall weight of construction machinery products is reduced by 17~40 and the service life is increased by 3~4 times.