MoS_2/Ti复合膜的摩擦磨损研究

采用直流磁控溅射方法在SKD-11钢的表面沉积一层MoS2/Ti复合膜,选择沉积厚度为1μm和2μm的复合膜进行摩擦磨损实验,结果表明,MoS2/Ti复合膜为纳米复合膜,能大大降低钢表面的摩擦系数,改善钢的摩擦性能。适当增加膜的厚度,有利于提高钢的抗磨损性能。     

Surface Hardening of High-Strength Low Alloy Steels (HSLA) Dual-Phase Steels by Ball Burnishing Using Factorial Design

Burnishing is used increasingly as a finishing operation which gives additional advantages such as increased hardness, fatigue strength, and wear resistance. Experimental work based on 3⁴ factorial design was carried out to establish the effects of ball burnishing parameters on the surface hardness of high-strength low alloy steels (HSLA) dual-phase (DP) steel specimens. Statistical analysis of the results shows that the speed, feed, lubricant and ball diameter have significant effect on surface hardness.     

Study on laser-alloyed self-lubricating anti-wear composite coating after ageing treatment

The NiCr/Cr₃C₂-10CaF₂ (wt-%) composite coatings were fabricated on Ti-6Al-4V alloy by laser surface alloying. Ageing treatments were performed at 600°C for 0, 24, 48 and 96?h, respectively. Microstructure and tribological properties of the as-laser-alloyed and aged composite coatings were investigated systematically. Results showed that microstructure became more homogeneous after ageing at 600°C for 48?h. Wear rates and friction coefficients of the aged composite coatings were slightly higher than that of the as-laser-alloyed coating. It indicates that microstructure and tribological properties of the composite coatings present good high-temperature stability.     

聚醚醚酮及其复合材料摩擦学研究近况

近年来 ,国内外的摩擦学研究者对聚醚醚酮 (PEEK)及其复合材料的摩擦学行为进行了广泛的研究 ,目的是在保持 PEEK其它优越性能的基础上 ,使其减摩和抗磨性能有所提高 ,以扩展这一新型工程塑料的应用领域。本文对 PEEK及其复合材料的摩擦学研究近况进行了综述。     

Tribological behaviour of MoS2/Au coatings

This study aims to enhance the endurance of MoS₂ coating by applying a thin layer of Au (∼ 80 nm) on MoS₂ surface. Experimental results show that the addition of Au film increases the endurance of MoS₂/Au over equivalent coatings without Au. The friction coefficient rapidly decreases to a stable value (μ ∼ 0.045) after about 100 cycles sliding. After more than 15,000 cycles, the friction coefficient gradually increased to a second stable value (μ ∼ 0.15). An average endurance of over 50,000 cycles was measured in this case. The Au or Au-MoS₂ composite layer can effectively prevent oxygen or moisture reaction with MoS₂ and hence significantly increases the wear life.     

Holistic Analysis of the Tribological Interfaces of an Axial Piston Pump – Focusing on the Pump Efficiency

Research work performed on an axial piston pump is shown in a holistic manner, analyzing each lubricating interface by linking their gap height and temperature behavior to the overall pump efficiency. The temperature field and dynamic fluid film height were measured in two of the three lubricating interfaces. This is the first time that the temperature fields and gap heights were simultaneously measured in two of the main three interfaces of an axial piston machine. For a deeper analysis of the measurement data, all gaps were simulated with a numerical tool which takes solid body deformation due to temperature and pressure loads into account. This unique combination of both extensive measurement data and sophisticated simulation resulted in novel trends that clarify the complex phenomena occurring in these hydrostatic fluid films.     

Nanoindentation in more than one dimension – Experimental challenges and opportunities

The current status of nanoindentation apparatus and the requirements for extension to more than one dimension of loading is described. It is possible, though not trivial, to adequately characterise the stiffnesses and couplings present in a frictional contact and thus expand the present use of nanoindentation to important new areas. The example of static friction is discussed to show that complete machine characterisation is required if true interface mechanical properties and friction coefficients are to be correctly measured.