电弧离子镀沉积TiN/AlN-TiAlN复合膜的耐磨性

采用高纯铝、钛靶材,通过电弧离子镀工艺在TC4基材上沉积制备了TiN/AlN-TiAlN复合多层膜,用HV-1000型显微硬度计测试了膜层的硬度,用球盘磨损试验对比研究了膜层和基材的耐磨性。结果表明:膜层硬度为2856HV,耐磨性相比基材提高6倍以上。     

不锈钢的电火花表面强化

以1Cr18Ni9Ti不锈钢为基材,采用电火花堆焊技术,研究堆焊后微观组织和显微硬度的变化.结果表明,堆焊层晶粒比基体晶粒细小,显微硬度高于基体.电火花堆焊可以改善不锈钢的表面耐磨性.     

激光熔凝高速火焰喷涂CoNiCrWC涂层组织与性能的研究

利用高速火焰喷涂在304不锈钢表面制备CoNiCrWC涂层,再利用5kW横流CO2激光对涂层熔凝。通过扫描电镜（SEM）观察熔凝层组织结构,测试并分析熔凝层显微硬度、耐磨性。实验结果表明,激光熔凝层与基材形成良好的冶金结合,熔凝层组织均匀：熔凝层显微硬度平均硬度为HV0．2964．314,明显高于基材硬度;在相同的奈件下,熔凝层的耐磨性比基体有了明显的提高。磨损体积减少了约89％。通过对磨损后的试样进行粗糙度观察后表明,涂层具有更平滑的表面。     

基于挤压应力条件的凸轮基圆半径的设计理论与方法

凸轮机构的使用寿命很大程度上取决于凸轮的强度和耐磨性，而这些性能参数又与凸轮所受挤压应力有关。由于凸轮的强度和耐磨性要到凸轮轮廓曲线设计毕之后才能计算，当现凸轮的强度和耐磨性不能保证凸轮机构的使用寿命时，就必须重新对凸轮曲率半径进行设计，因而造成浪费。     

采煤机导向滑靴新材料的强度与耐磨性研究

对国际先进采煤机中导向滑靴材料的化学成分和硬度进行测试分析,在此基础上查阅相关资料并进行配比试验,最终选用一种具有优良力学性能的CrNiMo系低碳合金钢作为导向滑靴的基材。通过试验测试了4种铁基熔覆层材料的耐磨性和硬度,确定了一种硬度高、摩擦因数小、耐磨性好的铁基合金粉末熔覆材料。通过试制,并经工业性试验验证,确认新研制的导向滑靴材料耐磨性好、强度高,完全满足1000万t级矿井高产高效综采工作面的要求。     

圆柱凸轮沟槽高频淬火感应器的研究

目前,凸轮分度机构已成为许多高效、高精度自动机、半自动机和自动生产线中不可缺少的关键部件。凸轮工作表面既要受到摩擦,还要承受冲击,承受着比心部高的应力,从而影响凸轮分度机构的使用寿命。要提高凸轮分度机构的使用寿命,就必须要求在凸轮工作表面的有限深度范围内具有高的强度、硬度和耐磨性,而其心部又要有足够的塑性和韧性,以承受一定的冲击力。要同时满足这两方面的要求,最好的办法就是在保证凸轮心部强度和韧性的前提下,对凸轮沟槽进行热处理强化。     

合金成分对激光熔覆TiC-TiB_2复合涂层组织性能影响

为增强材料表面硬度和耐磨性,以Ti O2-Al-B4C-C作为粉末体系,利用激光熔覆技术在45#钢基材表面上制备了Ti C-Ti B2增强复合涂层,采用金相显微镜、扫描电镜(SEM)、X射线衍射仪(XRD)、显微硬度计和摩擦磨损试验机研究了不同含量的Ti O2-Al-B4C-C系合金粉末对涂层组织性能的影响。结果表明:复合涂层与基材冶金结合,无裂纹和气孔等缺陷,Ti C、Ti B2弥散分布于涂层中;随着Ti O2-Al-B4C-C系合金粉末含量的增加,涂层组织中Ti C、Ti B2及等轴晶的量逐渐增多;熔覆层的硬度也逐渐增加,当合金粉末含量为70Wt%时,熔覆层硬度最高,为基材的4倍。Ti O2-Al-B4C-C系合金粉末含量为50Wt%时,熔覆层磨损量最小,耐磨性最好     

激光功率对熔覆Ni基涂层性能的影响

为提高45号钢表面硬度和耐磨性,可以在45号钢的表面采用激光熔覆技术熔覆合金涂层提高其表面性能。镍基合金熔覆层硬度高、耐磨、抗腐蚀、抗弯曲、可以在极端环境下具有稳定的性能,但在激光熔覆层中易产生裂纹。为改善45钢表面性能,在相同的扫描速率下采用不同功率在其表面激光熔覆制备了Ni基(Ni60)复合涂层,对不同激光功率熔覆层的性能检测使用金相显微镜、显微硬度仪、扫描电镜。结果表明:随着激光功率的增加,表面粗糙度变大,熔覆层的宽度、高度、基材的熔化深度都有一定程度的增大,裂纹出现趋势减小。在45号钢上熔覆Ni60合金粉末可以提高基材表面显微硬度,熔覆层显微硬度高出基材显微硬度约700HV,激光熔覆技术在一定范围内可以实现对基材的表面硬化。     

胶印机递纸凸轮新材料

该项目研究了两种材料:一、硬度:HRC48-51耐磨性:与轴承钢滚子对磨时,比用GCr15淬火凸轮提高30％[σ_H]=1650MPa,安全系数≥3.17     

不同激光熔覆材料涂层的耐磨性能比较

本文研究了宽带激光熔覆不同熔覆材料的复合涂层的耐磨性能。结果表明:Ni60B熔覆层的硬度高于40Cr基材的硬度,Ni60B+WC梯度复合涂层具有最高的硬度,对于提高零件的抗磨损性能比较有利;Ni60B熔覆层和Ni60B+WC熔覆层均适合修复轴类零件;三层梯度复合涂层磨痕宽度最小,具有最好的耐磨性。     

The relationship between the abrasive wear resistance,hardness and microstructure of ferritic materials

The relationship between the abrasive wear resistance and bulk hardness of ferritic materials in the pearlitic and martensitic conditions has been investigated. For pearlitic materials the abrasive wear resistance and bulk hardness are dependent on the pearlite content and for martensitic materials the abrasive wear resistance and bulk hardness are dependent on the square root of the carbon content. Thus for each structure there is a linear relationship between abrasive wear resistance and bulk hardness, but it is suggested that the material microstructure has a greater influence on wear resistance than the bulk hardness.     

12CrNi3A凸轮轴渗碳激光强化复合处理工艺

对12CrNi3A凸轮轴渗碳激光强化复合处理进行了研究。研究结果表明,采取表面渗碳工艺增加表层的碳浓度,并通过采用合理有产的激光淬火处理工艺,获得理想的淬硬层分布,提高了表层的硬度,增强了凸轮轴表面的耐磨性和抗疲劳强度,解决了凸轮轴磨损失问题,是开发和应用激光表面热处理技术的一个新的尝试。     

Abrasive erosive wear of powder steels and cermets

Composite materials produced by powder metallurgy provide solutions to many engineering applications that require materials with high abrasive wear resistance. The actual wear behaviour of a material is associated with many external factors (abrasive particle size, velocity and angularity) and intrinsic material properties of wear (hardness, toughness, Young modulus, etc.). Hardness and toughness properties of wear resistant materials are highly dependent on the content of the reinforcing phase, its size and on the mechanical properties of the constituent phase. This study is focused on the analysis of the (AEW) abrasive erosive wear (solid particle erosion) using different wear devices and abrasives. Powder materials (steels, cermets and hardmetals) were studied. Wear resistance of materials and wear mechanisms were studied and compared with those of commercial steels. Based on the results of wear studies, surface degradation mechanisms are proposed. The following parameters characterizing the materials were found necessary in materials creation and selection: hardness (preferably in scale comparable with impact), type of structure (preferably hardmetal type) and wear parameters characterizing material removal at plastic deformation.     

Some aspects of solid particle erosion of cermets

The erosive wear resistance of cermets with different composition, structure and properties has been investigated. It was shown that the erosive wear resistance of cermets can not be estimated only by hardness, characterizing resistance to penetration. The differences in wear resistance between cermet materials with equal hardness levels can be attributed to differences in their resistance to fracture and fracture toughness. The mechanism of erosion depends first on testing conditions. The present paper discusses some features of the material removal process during particle-wall collision. Systematic studies of the influence of the impact variables on the collision process have been carried out.     

多组分纤维混杂增强树脂基摩擦材料研究

为提高摩擦材料高温下的摩擦磨损性能和摩擦因数的稳定性,利用正交试验法对多种纤维增强酚醛树脂基摩擦材料的配方进行优化设计,并通过极差分析,探讨多种纤维及含量对摩擦材料性能的影响及摩擦材料的磨损机制.研究表明:混杂纤维增强树脂基摩擦材料有着优异的耐磨性.陶瓷纤维硬度较高,开散混料后能够均匀分布在树脂基体内,对酚醛树脂基摩擦...     

Tribological Behavior of New Martensitic Stainless Steels Using Scratch and Dry Wear Test

This paper focuses on the tribological characterization of new martensitic stainless steels by two different tribological methods (scratch and dry wear tests) and their comparison to the austenitic standard stainless steel AISI 316L. The scratch test allows obtaining critical loads, scratch friction coefficients, scratch hardness and specific scratch wear rate, and the dry wear test to quantify wear volumes. The damage has been studied by ex situ scanning electron microscopy. Wear resistance was related to the hardness and the microstructure of the studied materials, where martensitic stainless steels exhibit higher scratch wear resistance than the austenitic one, but higher hardness of the martensitic alloys did not give better scratch resistance when comparing with themselves. It has been proved it is possible to evaluate the scratch wear resistance of bulk stainless steels using scratch test. The austenitic material presented lower wear volume than the martensitic ones after the dry wear test due to phase transformation and the hardening during sliding.     

Three-body impact wear study on conventional and new P/M + HIPed wear resistant materials

A new hammer-mill type impact wear testing facility was built for impact wear testing and characterization. Tests with the hammer-mill impact wear device were carried out on conventional wear resistant materials such as Mn-steels of different compositions, white cast iron, and on new P/M+HIPed wear resistant materials. To verify the validity in using this laboratory wear testing apparatus, wear behavior and worn surfaces obtained on conventional and new Mn-steels generated from this device were compared with wear phenomena and worn surfaces developed in industrial applications, i.e. from certain types of rock crushers. The strain hardening effect in different Mn-steel grades was studied first. Second, the wear resistance of materials with different properties was studied using two different grades of abrasive. With silica sand (high hardness, low compressive strength), conventional Mn-steel and white cast iron perform in a manner comparable with the P/M+HIPed materials. With volcanite sand (low hardness, very high compressive strength), the P/M+HIPed wear resistant materials appear to have the best wear resistance.     

Principles of abrasive wear

The mechanisms of abrasive wear are reviewed and laboratory test methods assessed. The results of abrasive wear tests on technically pure metals, heat treated steels, cold work hardened materials, hard wear resistant materials and minerals against fixed abrasive grains are discussed. The correlation between abrasive wear resistance and the physical properties of materials is established; the effect of the relative hardness of the abrasive and impact loading is considered. The basic principles of abrasive wear derived are outlined.     

Surface wear characteristics of some hard carbons

The surface resistance to damage of homogeneous hard carbons such as glassy low temperature isotropic pyrolytic (LTI) and Ceraphite carbons have been determined by the falling abrasive particle test using SiC grit. Surfaces prepared from within the bulk of the glassy carbon specimens exhibit wear resistance proportional to their microindentation hardness but material near their virgin surfaces shows a lower resistance to this low velocity impact wear. Both pure and silicon-alloyed LTI carbons and Ceraphite material show considerably greater wear than the bulk glassy carbons of the same hardness. However, all of the hard carbons exhibit much greater surface damage resistance than other materials of comparable hardness such as mild steel or soda-lime glass. Microscopic surface examination indicates that brittle fracture is the main wear mode of the hard carbons in this test and the results are interpreted in terms of the microstructural features and characteristic elasticity properties of these solids.     

激光热处理在汽油机凸轮轴上的应用研究

对稀土镁球铁凸轮轴激光热处理硬化的组织和生进行了分析，并探讨了磨损机理，激光处理后的凸轮轴变形小，具有良好的耐磨性，这对实际应用很有意义。