Korim Nada S, Elsayed Ayman, Hu Lianxi
School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Faculty of Energy Engineering, Aswan University, Aswan 81528, Egypt.
Materials (Basel). 2022 Aug 20;15(16):5750. doi: 10.3390/ma15165750.
A Cu-15Fe alloy was fabricated using a powder metallurgy (PM) route, with the addition of different solid lubricants (i.e., paraffin wax (PW) and stearic acid (SA) as well as their composites (PW+SA)). Green compacts were produced via cold compaction at different pressure levels of 50 MPa, 200 MPa, and 350 MPa, then sintered for 60 min under vacuum at 1050 °C. The systematic evolution of the densification, porosity, and pore-size behavior were studied. Vickers Hardness Tests were used to measure hardness. The analysis of the morphological alterations was performed using scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. Moreover, under dry sliding conditions, pin-on-disk wear tests were conducted in order to determine tribological properties such as the coefficient of friction (µ), specific wear rate (K), and friction temperature gain. Results revealed that the lubrication process and compaction pressure play a crucial role in defining the characteristics of the final compact. Higher sintered densities and hardnesses were achieved at 50 MPa when PW was used as a solid lubricant, and became reduced as the compaction pressure increased. In contrast, in the case of SA, higher sintered densities and hardnesses were obtained at a compaction pressure of 350 MPa, and increased with increasing pressure. Moreover, PW samples exhibited lower coefficients of friction and wear properties. The addition of SA improves the wear loss of friction materials as well as their coefficients of friction. Compared to blank and PW samples, SA samples show a nearly 50% reduction in wear rate.
采用粉末冶金（PM）工艺制备了一种Cu-15Fe合金，并添加了不同的固体润滑剂（即石蜡（PW）和硬脂酸（SA）及其复合材料（PW+SA））。通过在50MPa、200MPa和350MPa的不同压力水平下进行冷压制成生坯，然后在1050℃真空下烧结60分钟。研究了致密化、孔隙率和孔径行为的系统演变。使用维氏硬度测试来测量硬度。使用扫描电子显微镜（SEM）和X射线衍射（XRD）技术对形态变化进行分析。此外，在干滑动条件下，进行销盘磨损试验，以确定摩擦学性能，如摩擦系数（µ）、比磨损率（K）和摩擦温度升高。结果表明，润滑过程和压制压力在确定最终压坯的特性方面起着至关重要的作用。当使用PW作为固体润滑剂时，在50MPa下可获得更高的烧结密度和硬度，且随着压制压力的增加而降低。相比之下，对于SA，在350MPa的压制压力下可获得更高的烧结密度和硬度，并随压力增加而升高。此外，PW样品表现出较低的摩擦系数和磨损性能。SA的添加改善了摩擦材料的磨损损失及其摩擦系数。与空白和PW样品相比，SA样品的磨损率降低了近50%。
