Microstructure and dry sliding wear resistance of Moss-toughened Mo2Ni3Si metal silicide alloys

A wear resistant Mo₂Ni₃Si-based metal silicide alloy toughened by molybdenum-based solid solution (Mo_ss) was fabricated by the laser melting deposition (LMD) manufacturing process. Microstructure of the alloy is composed of Mo_ss primary dendrites and the matrix of the single phase Mo₂Ni₃Si. Wear resistance and friction coefficient of the alloys were evaluated under metallic dry sliding wear test conditions as a function of contact load. Results showed that the alloys have a low friction coefficient and outstanding wear resistance due to the high hardness of Mo₂Ni₃Si matrix and the high strength, ductility and toughness of Mo_ss dendrites. The wear rate and the friction coefficient of alloys are extremely insensitive to the contact load owing to the abnormal hardness–temperature relation of Mo₂Ni₃Si. The Mo_ss dendrite played the role of trapping micro-cracks and restraining brittle spalling of the Mo₂Ni₃Si matrix during wear process and improved the wear properties of Mo_ss-toughened Mo₂Ni₃Si alloy.     

Room-temperature dry sliding wear behavior of γ-Ni/Mo2Ni3Si metal silicide “in situ” composites

Ni-base solid solution (γ) toughened Mo₂Ni₃Si metal silicide “in situ” composites were fabricated with different volume fraction of Mo₂Ni₃Si primary dendrite uniformly distributed in irregular Mo₂Ni₃Si/γ eutectic matrix. Results of room-temperature dry sliding wear tests indicated that the composite with a medium volume fraction of primary Mo₂Ni₃Si phase possessed the best wear resistance by optimum combination of the unique mechanical property of Laves phase Mo₂Ni₃Si and toughening effect of ductile γ phase. The primary wear mechanism is microplowing and soft-abrasion of the interdendritic Mo₂Ni₃Si/γ and subsequent brittle fracture of the hard Mo₂Ni₃Si primary dendrites. Ductile γ phase provided good toughening effect to Mo₂Ni₃Si Laves phase during dry sliding wear process.     

钛合金表面激光熔敷Ti2Ni3Si/NiTi耐磨涂层组织与耐磨性能

以Ti-50Ni-10Si合金粉末为原料，利用激光熔敷技术在钛合金BT9基材表面制得由Ti2Ni3Si初生树枝晶和枝晶间Ti2Ni3Si／NiTi共晶组织组成的耐磨材料涂层，研究了涂层的显微组织及室温耐磨性能。结果表明，该涂层在室温干滑动磨损条件下具有优异的耐磨性能和良好的载荷特性。     

Elevated temperature wear behaviors of a Co–Mo–Si ternary metal silicide alloy

Wear resistant Co–Mo–Si ternary metal silicide alloy consisting of Co₃Mo₂Si primary dendrite and the interdendritic ductile Co-base solid solution (Co_ss) was designed and fabricated by the laser melting process. The alloy exhibited strong abnormal load- and temperature-dependence of wear under elevated temperature metallic sliding wear test conditions.     

激光熔覆Mo2Ni3Si／NiSi金属硅化物复合材料涂层组织与耐磨性

以39Mo-35Ni-26Si(w％)合金粉末为原料，采用激光熔覆技术，在1Cr18Ni9Ti不锈钢基材表面翩得以Mo2Ni3Si金属硅化物为初生相，以Mo2Ni3Si／NiSi共晶相为基体的金属硅化物耐磨复合材料涂层。涂层的常温干滑动磨损试验结果表明，在磨损过程中，Mo2Ni3Si／NiSi共晶相轻微地优先磨损，Mo2Ni3Si金属硅化物微微凸出于磨损表面，起到抗磨的骨干作用。由于Mo2Ni3Si金属硅化物具有很高的硬度和很强的原子间键合力，在磨损过程中难于变形和粘着，激光熔覆Mo2Ni3Si／NiSi金属硅化物复合材料涂层具有优异的耐磨性，与1Cr18Ni9Ti标样相比，涂层的耐磨性提高了56倍。     

A wear resistant ductile metal-toughened Cr13Ni5Si2 ternary metal silicide alloy

A ductile metal-toughened Cr–Ni–Si ternary metal silicide wear resistant alloy with a dual-phase microstructure consisting of Cr₁₃Ni₅Si₂ ternary metal silicide primary dendrites and the interdendritic nickel-base solid solution (γ) was designed and fabricated by the laser melting/continuous deposition process. Wear resistance of the γ-toughened Cr₁₃Ni₅Si₂ intermetallic alloy was evaluated on an MM-200 block-on-wheel dry sliding wear tester at room temperature. The γ-toughened Cr₁₃Ni₅Si₂ intermetallic alloy has excellent wear resistance and extremely low load-sensitivity of wear under dry sliding wear test conditions due to the inherent high hardness, abnormal hardness–temperature relation and strong covalent-dominant atomic bonds. The isolated toughening γ phase played a positive role in reducing volume wear rate by retarding crack propagation and preventing pull-out of the broken Cr₁₃Ni₅Si₂ fragments from the wear surface.     

激光熔敷Ti5Si3／NiTi金属间化合物复合材料涂层组织与耐磨性

以Ti14Si6Ni80合金粉末为原料，利用激光熔敷技术在BT9钛合金表面制得以金属硅化物Ti5Si3为增强相、以金属间化合物NiTi为基体的快速凝固金属间化合物复合材料涂层，分析了该涂层的显微组织，在室温干滑动磨损条件下测试了其耐磨性。研究结果表明，涂层硬度高、组织致密、与基材之间为完全冶金结合，在干滑动磨损试验条件下具有较好的耐磨性。涂层具有优异耐磨性的主要原因是作为耐磨增强相的金属硅化物Ti5Si3具有高硬高耐磨的特性，在涂层中起到了抗磨骨干作用，同时作为涂层基体的金属间化合物NiTi由于具有极强的原子结合键及应力诱发马氏体相变特性，本身具有优异的耐磨性，在摩擦过程中对耐磨增强相Ti5Si3起到了强力支撑作用。     

Microstructure and dry sliding wear resistance of a Cr13Ni5Si2 ternary metal silicide alloy

Wear resistant Cr–Ni–Si metal silicide alloy with a microstructure primarily consisting of ternary metal silicide Cr₁₃Ni₅Si₂ primary dendrites was fabricated by the laser melting (Lasmelt) process using Cr–Ni–Si elemental powder blends as the precursor materials. Microstructure of the alloy was characterized by optical microscopy, scanning electron microscopy, X-ray diffraction and energy dispersive X-ray analysis. Wear resistance of the Cr₁₃Ni₅Si₂ alloy was evaluated under dry sliding wear test conditions at room temperature. Results indicate that the Cr₁₃Ni₅Si₂-based metal silicide alloy has excellent wear resistance under dry sliding wear test conditions.     

激光熔化沉积Ti5Si3/NiTi双相金属间化合物合金耐磨性能

采用激光熔化沉积工艺制备出以块状Ti5Si3过渡金属硅化物为初生相、以Ti5Si3/NiTi共晶为基体的双相金属间化合物耐磨合金,在室温干滑动磨损条件下测试了Ti5Si3/NiTi合金的耐磨性能并讨论了其磨损机制。结果表明,由于Ti5Si3/NiTi合金良好的强韧性配合以及在磨损过程中磨损表面上形成了“无组织特征”的表面高硬度层,对合金有保护作用,合金在室温干滑动磨损条件下具有优异的耐磨性能和很低的载荷敏感性     

激光熔炼W/W2Ni3Si金属硅化物“原位”复合材料的耐磨性

采用水冷铜模激光合金熔炼炉制备了以初生w树枝晶为增强相、以w2Ni3Si三元金属硅化物为基体的金属硅化物“原位”耐磨复合材料．分别在室温干滑动磨损及600℃高温滑动磨损条件下测试了上述W／W2Ni3Si金属硅化物“原位”增强耐磨复合材料的耐磨性，并讨论了其磨损机理．结果表明，上述金属硅化物耐磨复合材料在室温干滑动磨损和高温滑动磨损条件下均具有优异的耐磨性能．     

钛合金激光熔覆TiB-TiC增强TiNi-Ti2Ni金属间化合物复合涂层的组织和耐磨性（英文）

以Ti＋Ni＋B4C粉末混合物为原料,利用激光熔覆技术在TA15钛合金基材表面制得TiB-TiC共同增强TiNi-Ti2Ni金属间化合物复合涂层。采用OM、SEM、XRD、EDS及AFM等手段分析激光熔覆涂层的显微组织及磨损表面,测试涂层的室温干滑动磨损性能。结果表明,激光熔覆TiB-TiC增强TiNi-Ti2Ni金属间化合物复合涂层熔覆具有独特的显微组织,菊花状的TiB-TiC共晶均匀分布在TiNi-Ti2Ni双相金属间化合物基体中。由于高硬、高耐磨TiB-TiC陶瓷相与高韧性TiNi-Ti2Ni双相金属间化合物基体的共同配合,激光熔覆涂层表现出优异的耐磨性。     

激光熔炼Ti5Si3／NiTi金属间化合物合金的组织及耐磨性

设计并利用激光熔炼技术制备出了以Ti5Si3为增强相、以NiTi为基体的金属间化合物新型耐磨合金，研究了增强相Ti5Si3的含量对合金显微组织、显微硬度及耐磨性能的影响。结果表明，随Ti5Si3含量的增加，合金显微组织由亚共晶向共晶、过共晶转化，增强相Ti5Si3由细层片状共晶相向块状初生相转变，合金显微硬度随之显著提高；在室温干滑动磨损条件下，Ti5Si3／NiTi金属间化合物合金具有优异的耐磨性，并随Ti5Si3增强相的增加而显著提高。Ti5Si3增强相的高硬度和NiTi基体的高韧性及伪弹性效应是该合金具有优异耐磨性能的主要原因。     

Microstructure and wear property of laser-clad Co3Mo2Si/Coss wear resistant coatings

Novel wear resistant Co₃Mo₂Si/Co_ss coatings consisting of a microstructure of hard and strong Co₃Mo₂Si intermetallic phases embedded in the ductile Co-base matrix were fabricated on austenite stainless steel by the laser cladding process from the Co-Mo-Si powder blend precursor. The microstructures of the coatings were characterized by optical microscopy (MO), X-ray diffraction (XRD), and scanning electron microscopy (SEM) with an energy-dispersive X-ray analysis (EDX). The wear resistance of the coatings was evaluated in a dry sliding wear test condition at room temperature. Results indicated that the laser-clad Co₃Mo₂Si/Co_ss coatings exhibited very excellent wear resistance against abrasive and adhesive wear.     

激光熔化沉积NiTi/Ni3 Ti金属间化合物合金的显微组织和耐磨性

利用激光熔化沉积技术制备出分别以NiTi和Ni3Ti为初生相的NiTi/Ni3Ti金属间化合物耐磨合金,采用XRD、OM、SEM、EDS等手段分析合金的组织,测试合金的室温干滑动磨损性能。结果表明,其室温干滑动磨损机制为软磨料磨损和氧化磨损;对于以Ni3Ti为初生相的合金,其室温干滑动磨损机制在中低负荷下为氧化磨损和显微切削,在高负荷下则是Ni3Ti的显微切削;以NiTi为初生相的NiTi/Ni3Ti金属间化合物合金具有更好的抗室温摩擦磨损性能。     

Ti2Ni3Si/NiTi金属间化合物合金在H2SO4溶液中的腐蚀行为

利用激光熔炼材料制备技术,制得了由三元金属硅化物Ti2Ni3Si初生枝晶和枝晶间Ti2Ni3Si/Ti共晶组成的金属间化合物耐磨耐蚀合金;采用极化曲线、塔菲尔图(Tafel Plot)和交流阻抗(EIS)等技术,研究了合金在1 mol/L H2SO4溶液中的电化学腐蚀行为以及Ti含量对合金组织与耐蚀性的影响.结果表明:由于表面形成的稳定钝化膜及Ti2Ni3Si和NiTi的高化学稳定性,使合金在1 mol/L H2SO4溶液中具有优异的耐蚀性,且随着Ti含量的升高,合金的耐蚀性略有提高.     

激光熔敷NiTi/Ni3Ti金属间化合物复合材料涂层组织及耐磨性

以Ni79Ti21（wt％）合金粉末为原料,采用同步送粉激光熔敷技术在BT20钛合金表面制备出NiTi／Ni3Ti金属间化合物复合材料涂层,分析了该涂层的显微组织,测试了该涂层的室温干滑动磨损性能。结果表明,激光熔敷涂层组织均匀致密,与基材呈良好的冶金结合,具有优良的抗滑动磨损性能。     

Microstructure and high-temperature wear behavior of laser clad Ni-Ti-Si ternary metal silicide coatings

Ni-Ti-Si ternary metal silicide coatings were fabricated on AISI 304 stainless steel by laser cladding process. The coatings consisted of Ni₁₆Ti₆Si₇ primary dendrite and interdendritic Fe-Ni-based solid solution γ and exhibited excellent abrasive and adhesive wear resistance under high temperature metallic dry sliding wear conditions. The excellent wear properties were attributed to the high hardness and covalent dominant atomic bond of the metal silicide Ni₁₆Ti₆Si₇. The dominant wear mechanism of the coating were delamination of the coating and material transfer from the mating surface.     

Microstructure and tribological properties of Cuss-toughened Cr–Cu–Si metal silicide alloys

Wear resistant Cr–Cu–Si metal silicide alloys with different Cu contents were fabricated by the laser melting process. The Cr–Cu–Si alloys have a similar microstructure consisting of the Cr₅Si₃/CrSi dual-phase primary dendrites and the interdendritic Cu-based solid solution (Cu_ss). The Cu content has no effect on the phase constitutions of the alloys. The Cr₅Si₃/CrSi dendrite volume fraction and hardness of the Cr–Cu–Si alloys decrease with the increasing Cu content. Wear test results indicate that all the Cu_ss-toughened metal silicide alloys have excellent wear resistance and low coefficient of friction. Wear resistance increases and friction coefficient decreases with the decreasing Cu content.     

钛合金表面激光熔敷Cr13Ni5Si2基金属硅化物涂层组织与耐磨性

以Cr-Ni-Si合金粉末为原料、利用激光熔敷技术在钛合金表面上制得了Cr13Ni5Si2基金属硅化物冶金涂层，在于滑动磨损条件下测试了该涂层的耐磨性能。结果表明，激光熔敷Cr13Ni5Si2基金属硅化物涂层组织主要由Cr13Ni5Si2初生树枝品及少量Cr13Ni5Si2／Cr13Ni5Si2共晶组成，涂层在干滑动磨损条件下具有优异的耐磨性能。     

不同激光功率下镁合金表面激光熔覆Ni60合金涂层的显微组织和磨损性能

为提高镁合金表面的耐磨性,利用5kW横流连续CO2激光器在AZ31B镁合金表面熔覆Ni60合金粉末,制备了无裂纹、气孔等缺陷的熔覆层。分析讨论了不同激光功率下熔覆层的显微组织和磨损性能。结果表明:熔覆层的显微组织为典型的枝晶状态,且随着激光功率的增加,枝晶尺寸增加;不同的激光功率下,熔覆层都由Mg、MgNi2、Mg2Ni3Si、Mg2Ni、Mg2Si和FeNi组成,但当激光功率增加时,Mg相含量逐渐减小,其它相含量逐渐增多。在枝晶细化和各种金属间化合物的共同作用下,熔覆层的显微硬度和耐磨性能都得到提高,且激光功率P=3 000W时,提高程度最大,即显微硬度提高了840%～1 102%,磨损失量是原始AZ31B镁合金的8.57%。