In order to investigate the influence of molding temperature on the mechanical and tribological properties of modified phenolic resin-based friction materials, six kinds of friction materials (FMs) with different molding temperatures were prepared by a hot-pressing process using melamine-modified phenolic resin (MPR) and boron-modified phenolic resin (BPR) as binders. The experimental results show that the density change of the friction materials is very small. The hardness, compressive strength, and compressive modulus decrease with the increase of molding temperature, and the impact strength decreases with the increase of molding temperature. The coefficient of friction (COF) of the melamine-modified phenolic resin-based friction material with a molding temperature of 160 °C is higher, and the stability is the largest. The COF of the boron-modified phenolic resin-based friction material decreases with the increase of the molding temperature, and the COF of each sample has a large difference. When the molding temperature is 160 °C, the COF of the samples is stable between 0.409 and 0.462 at different initial braking speeds. Relatively speaking, the sample with a hot-pressing temperature of 160 °C has better comprehensive properties, the wear mechanism is mainly abrasive wear and adhesive wear, and the large-area continuous friction film can stabilize the COF.

In the present study, the composites have been prepared using vacuum hot pressing process technique. The influence of 2.0 wt.% nanometric SiC particles (n-SiC_p) on the microstructure and fracture mechanism of 7075 aluminum alloy was studied by means of metallographic microscope, scanning electron microscope (SEM), energy-dispersive spectrometer (EDS), X-ray diffraction (XRD), laser scanning confocal (LSC). The results indicate that SiC_p fill at grain boundaries dispersing evenly and nail to aluminum grains which sizes have been reduced successfully, that making the organization tighter, the gaps fewer and the surface rougher. Meanwhile, phases (MgZn₂) precipitated from the 7075 aluminum alloy were been detected. The grain bonding states of matrix alloys are strengthened by the combination of fine grains strengthening and dispersion strengthening and thus affect the fracture morphology. The micro-fracture mechanism of 7075 aluminum alloy is micro-porous aggregation fracture, however, the 7075 aluminum matrix composites (AMCs) are quasi cleavage fracture.

After hot rolling and multipass cold rolling experiment, the hot rolled sheet and the sheets with reduction ratios of 20% and 40% of 301L stainless steel were obtained. The effect of cold rolling reduction ratio on microstructure of 301L stainless steel was investigated by metallographic analysis, XRD analysis and TEM analysis. The research shows that carbides precipitate along the austenite phase interface in the hot rolled specimen. Crystalline grains are refined by cold rolling: their average grain size decreases from 91.9 to 17.3 nm as the reduction ratio increases, which is accompanied by the blocking of dislocations.