扩散退火温度对热浸镀铝钢高温磨损性能的影响  

Influence of Diffusion Annealing Treatment Temperature on High Temperature Wear Resistance of Hot Dipping Aluminized Steel

作　　者：范彬[1,2] 文明才[1] 廖建勇[1] 

机构地区：[1]湖南城市学院机械与电气工程学院,湖南益阳413000 [2]中南大学机电工程学院,湖南长沙410083

出　　处：《热加工工艺》2016年第4期212-216,共5页Hot Working Technology

基　　金：湖南教育厅资助项目(14C0208)

摘　　要：研究了经650、950℃扩散退火5 h后的热浸镀铝钢,在环境温度400℃、不同载荷作用下的磨损行为,并探讨了其磨损机理。结果表明,经650℃扩散退火处理的热浸镀铝钢的镀层主由脆性相Fe_2Al_5组成;其磨损率随载荷的增大而增大,主磨损机制为氧化磨损和剥落磨损。经950℃扩散退火处理后的镀层均由韧性相FeAl和Fe_3Al构成;当载荷低于200 N时,其磨损率几乎不随载荷变化,且保持在很低的水平;其优异的耐磨性源于磨面处形成了厚1~2μm、含大量Al2O3和Fe2O3及少量W、Mo的氧化物的摩擦氧化层,主磨损机制为氧化轻微磨损。当载荷增加至250 N时,45钢基体发生热软化,摩擦层不稳定而剥落,基体发生塑性挤出。Wear behavior of hot diping aluminized （HDA） steel processed at 650 ℃ and 950 ℃ for 5 h under different testing loads in 400 ℃ was investigated thoroughly, the wear mechanism was also explored. Results show that HDA coating is mainly consisted of brittle phase Fe2A15, as the diffusion annealing temperature is 650 ℃, its wear rate increases with the increase of loads. The main wear mechanism is oxidation wear and spalling wear. HDA coating is chiefly composed of ductile phase FeAl and Fe3Al, as the diffusion annealing temperature is 950 ℃. While the loads below 200 N, the wear rate hardly changes with the increase of loads, keeping in an extremely low level. Its excellent wear resistance owes to a 1-2 μm thick tribo-layer formes on the worn surface, mainly composed of Al2O3, Fe2O3, and a small mount of oxides of W and Mo. The main wear mechanism is oxidative mild wear. When testing load increases to 250 N, the tribo-layer is peeled off due to its unstability as 45 steel substrate thermal softened, and the substate is extruded plastically.

关 键 词：扩散退火 热浸镀铝钢 氧化轻微磨损 摩擦氧化层 

分 类 号：TG115.58[金属学及工艺—物理冶金]