飞机起落架用300M超高强度钢的表面脱碳行为研究  

Research on Surface Decarburation Behavior of 300M Ultra High Strength Steel for Aircraft Landing Gear

作　　者：张海成 肖细军 曾德涛 ZHANG Haicheng;XIAO Xijun;ZENG Detao(China National Erzhong Group Deyang Wanhang Die Forging Co.,Ltd.,Deyang 618000,China;Changsha Landing Gear Branch of AVIC Aircraft Co.,Ltd.,Changsha 410000,China)

机构地区：[1]中国第二重型机械集团德阳万航模锻有限责任公司,四川德阳618000 [2]中航飞机股份有限公司长沙起落架分公司,湖南长沙410000

出　　处：《热加工工艺》2024年第12期120-124,128,共6页Hot Working Technology

基　　金：四川省重大科技专项项目(2022ZDZX0040)。

摘　　要：300M超高强度钢具有优异的综合性能,被广泛应用于飞机起落架系统中各种重要承力锻件的制造。在热加工生产流程中,长时间高温加热和热处理,材料不可避免会发生脱碳现象,脱碳会显著恶化钢质锻件表面的微观组织和力学性能,是飞机起落架零件上不允许出现的一种材料缺陷。通过箱式电阻炉等温加热实验,利用金相法,研究了保温时间、加热温度和热处理工艺等工艺参数对300M超高强度钢脱碳行为的影响。结果表明:当加热温度为1160℃时,在0.5~2 h保温时间范围内,300M超高强度钢的脱碳层深度随着保温时间的延长而增大,但是脱碳层深度增长趋势随着保温时间的增加而变缓;当保温时间为2 h时,在800~1200℃加热温度范围内,脱碳层深度随着加热温度升高先增大后减小,当1100℃时脱碳层深度最大;不同热处理工艺下,不做热处理时300M超高强度钢的表面脱碳深度最小,而加热温度最高的正回火+淬回火热处理工艺的脱碳层深度最大。Due to the excellent comprehensive properties,300M ultra-high strength steel is widely used in the manufacturing of various important forging parts in the aircraft landing gear systems.During the hot working production process,long term high temperature heating and heat treatment inevitably leads to the decarburization of the material,which significantly influences the microstructure and mechanical properties of the steel forging surface.It is a material defect that is not allowed to appear on aircraft landing gear parts.In order to study the surface decarburation behavior of 300M ultra-high strength steel,the effects of heating time,heating temperature and heat treatment process were investigated by isothermal heating experiments in a box-type resistance furnace based on the metallographic method.The results show that when the heating temperature is 1160℃,within the range of 0.5-2 h of holding time,the depth of decarburization layer of 300M ultra-high strength steel increases with the extension of holding time,however,the growth trend of decarburization layer depth slows down with the increase of holding time;when the holding time is 2 h,within the heating temperature range of 800-1200℃,the depth of the decarburization layer increases firstly and then decreases with the increase of heating temperature,the depth of the decarburization layer reaches maximum value at 1100℃;under different heat treatment processes,the surface decarburization depth of 300M ultra-high strength steel is the smallest without heat treatment,while the decarburization layer depth is the highest under the heat treatment process condition of normalizing/tempering+quenching/tempering.

关 键 词：300M超高强度钢 脱碳 加热时间 加热温度 热处理 

分 类 号：TG142.1[一般工业技术—材料科学与工程]