电弧熔丝增材制造船用低合金高强钢组织与性能研究

Microstructure and mechanical properties of low-alloy high-strength steel for ship fabricated by wire-arc additive manufacturing

采用电弧熔丝增材制造技术,填充自制的船用低合金高强度钢丝材,制备了多道多层的钢墙体,并对其沉积态和退火态试样的组织与力学性能进行了研究。结果表明,采用电弧熔丝增材制造技术制备的低合金高强度钢墙体成形质量良好,层间实现了有效的冶金结合。沉积态试样的微观组织主要由粒状贝氏体和不规则的多边形铁素体组成,具有较高的强度、塑性和低温冲击韧性。经过400℃和600℃退火热处理后,马氏体-奥氏体组元不断发生分解,形成铁素体和许多细小的碳化物,使粒状贝氏体的数量减少,铁素体的数量增加,导致强度降低,塑性和低温韧性提高。

The multiple-pass multilayer steel wall was fabricated by wire-arc additive manufacturing(WAAM)technology using self-made low-alloy high-strength steel wire for ship.The microstructure and mechanical properties of the as-deposited and annealing heat treated samples were studied.The results showed that the low-alloy high-strength steel wall fabricated by WAAM had good forming quality and realized effective metallurgical combination between layers.The microstructure of the as-deposited sample was mainly composed of granular bainite and irregular polygonal ferrite,which had high strength,plasticity and good low temperature impact toughness.The martensite-austenite(MA)components were continuously decomposed to form ferrite and many fine carbides after annealing at 400°C and 600°C,which reduced the number of granular bainite and increased the number of ferrite,resulting in strength reduction and plasticity and low temperature toughness improvement.