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Ferro-phosphorus is an important industrial alloy, which plays a pivotal role in steelmaking, chemical industry, new energy and construction industry. The development and utilization of ferro-phosphorus can not only bring economic benefits to enterprises, but also contribute to the development of national economy. In this paper, the experiment was carried out under the conditions of T=1200℃-1400℃, R(CaO/SiO2)=1.0, t=60 min and C=12%. Phosphate rock and copper slag were used as raw materials, graphite was used as reducing agent, and ferrophosphorus was produced by reduction and roasting in a high-temperature energy-saving tubular furnace. The reduced samples were separated and ground, XRD, SEM and EDS were used to characterize ferrophosphorus and slag. The results showed that the main phase of ferrophosphorus obtained is Fe3P at T1300℃. After reduction, it was measured that the main component of the slag was silicate, mainly calcium metasilicate (CaSiO3) and a small amount of aluminum silicate.

Diamond films were deposited on 4H-SiC substrates by microwave plasma chemical vapor deposition (MPCVD). The substrate pretreatment method of electrostatic adsorption of seed crystals by nanodiamond suspensions was used, and the nucleation density of diamond on the substrate surface reached 10 ^10 /cm ^2 compared with ultrasonic seed crystals of diamond micro-powder suspensions, and continuous dense diamond films were formed in a shorter growth time. Scanning electron microscopy and Raman spectroscopy were used to characterize the changes of diamond grain morphology and quality with methane concentration, deposition time and substrate temperature during the growth process. The experimental results show that the methane concentration, deposition time and substrate temperature are the key factors affecting the grain shape and quality of diamond. And the best quality of diamond film is obtained at 850 °C substrate temperature.

Stainless steel is a notoriously difficult-to-machine material, with challenges such as hard-to-break chips and severe tool wear. To address these issues, a finishing indexable insert has been designed and developed specifically for stainless steel. This tool, named HMF, was compared to commercial tools (NF4, BF) in terms of its curved groove structure and cutting performance using SEM (scanning electron microscope Sigma500), 3D scanning (KEYENCE-VR 5000) and a profiler (Mitutoyo C-200). The HMF tool utilizes a curved edge with a curved chip breaker, and a chip-breaking bump on the tool nose. The groove parameters of the HMF insert are as follows: cutting edge angle of 12°, chip breaker groove width of 1.89 mm, back wall height of 0.095 mm, and anti-chip angle of 4°49’. 3D scanning of the chip break site reveals that the HMF chip break has a higher bump and a more pronounced chip rolling effect. HMF tool chip-breaking experiments show that it has ideal chip-breaking performance in the finishing range of ap = 0.6–1.0 mm, and f = 0.1–0.25 mm r ^−1 . Chip analysis shows that the HMF chip curl frequency increases and the chip curl is tighter as the feed rate increases, and the curl radius gradually decreases when the feed rate is greater than 0.15 mm r ^−1 . The results of the wear performance study are as follows: all three tools show rake face crater wear when cutting stainless steel. A small amount of built-up edge appears on the HMF cutting edge. The wear life of HMF is close to NF4 and better than BF; the wear of BF is faster in the later stages of wear.