等离子原位制备VC增强Al_(1.5)CoCrFeNi高熵合金熔覆层的组织与力学性能  

Microstructure and Mechanical Properties of VC Enhanced Al_(1.5)CoCrFeNi High-entropy Alloy Cladding Layers by Plasma in Situ Synthesis Technique

作　　者：王虎 秦晓婷[3] 王智慧[3] 贺定勇[3] WANG Hu;QIN Xiaoting;WANG Zhihui;HE Dingyong(College of Materials Engineering,North China Institute of Aerospace Engineering,Hebei Langfang 065000,China;Hebei Provincial Key Laboratory of Thermal Protection Materials,Hebei Langfang 065000,China;Faculty of Materials and Manufacturing,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北华航天工业学院材料工程学院,河北廊坊065000 [2]河北省热防护材料重点实验室,河北廊坊065000 [3]北京工业大学材料与制造学部,北京100124

出　　处：《表面技术》2025年第3期110-117,共8页Surface Technology

基　　金：中央引导地方科技发展资金项目(246Z1816G);北华航天工业学院科研基金项目(CXPT202402)。

摘　　要：目的制备不同含量碳化物增强BCC结构的高熵合金熔覆层,研究碳化物含量对其微观组织和力学性能的影响规律。方法在Q235钢表面采用等离子原位合成技术制备Al_(1.5)CoCrFeNi(VC)x(x为0、0.1、0.2、0.3)高熵合金熔覆层,研究VC含量对其物相组成、微观组织及力学性能的影响。结果在x=0时,熔覆层为简单体心立方(BCC)固溶体结构,微观组织呈典型的树枝晶,枝晶内为富含Al、Ni的BCC固溶体,枝晶间为富含Cr、Fe的BCC固溶体。在加入V、C后(x为0.1、0.2、0.3),物相组成转变为BCC相、原位合成的VC增强相及少量的σ相。VC呈颗粒状、长条状及十字状,主要偏聚于基体的树枝晶间,少数从枝晶内析出,且随着V、C含量的提高,VC的析出量逐渐上升。TEM结果显示,原位合成的VC增强相与基体之间的界面整洁,无反应物生成。当VC的含量x由0提高至0.3时,熔覆层的硬度由529.3HV增至829.8HV,磨损率由34.88mg/min降至2.45mg/min。在x=0时,熔覆层的磨损形式以微观切削为主,以多次塑性变形为辅;在原位合成VC增强相后(x为0.1、0.3),熔覆层的磨损形式以微观切削为主。结论原位合成VC对高熵合金起到了明显的强化作用,随着VC含量的增加(x为0~0.3),熔覆层的显微硬度和耐磨性逐渐增加。The work aims to prepare in situ carbide enhanced BCC structure high-entropy alloy cladding layers,and study the effect of design content of carbide on their microstructure and mechanical properties.Therefore,in situ VC enhanced Al_(1.5)CoCrFeNi(VC)x(x=0,0.1,0.2,0.3,mole ratio)high-entropy alloy were manufactured on the Q235 steel by plasma cladding.The effect of VC design content on their phases,microstructure,and mechanical properties were analyzed.Al,Co,Cr,Fe,Ni,vanadium-iron alloy(50%V,50%Fe)and high carbon ferrochrome(7%C,30%Fe,63%Cr)powders were mixed according to the atomic ratio of Al_(1.5)CoCrFeNi(VC)x(x=0,0.1,0.2,0.3,mole ratio).The particle size range of the above powders was 100-200 mesh.Q235 steel was selected as substrate,whose surface was polished and rinsed with acetone before plasma cladding.A plasma spray welding machine(PT-400E4-ST)was used to produce cladding layers.The phases,morphologies,and element compositions of cladding layers were analyzed by X-ray diffractometer(XRD,XRD-7000),scanning electron microscope(SEM,S-3400),energy dispersive spectrometer(EDS)and transmission electron microscope(TEM,JEM2100),respectively.The microhardness of cladding layers were measured by microhardness tester(HXD-1000).The wear properties of cladding layers were evaluated by abrasive wear testing machine(MLS-225).The results indicated that when x=0,the cladding layer was BCC solid-solution and its microstructure was typical dendrite structure.The dendrite was BCC solid-solution rich in Al and Ni,and the interdendrite was BCC solid-solution rich in Cr and Fe.After adding V and C(x=0.1,0.2,0.3),the diffraction peaks of cladding layers were composed of BCC solid-solution,VC and a fewσphases.The shape of VC was polygonal granular,long striplight and cross-dendrite.The VC mostly segregated at interdendrite,but only a few inside the dendrite.And with the increase of V and C content,the precipitation amount of VC also increased.TEM results indicated that the interface between the in situ VC and the matrix was clean

关 键 词：等离子熔覆 原位合成 高熵合金 VC 微观组织 力学性能 

分 类 号：TB331[一般工业技术—材料科学与工程]