International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The effect of individual additions of Ti and B into high chromium white cast irons (HCWCIs) on the structure, corrosion and selected mechanical properties was investigated. Two different heat treatments were applied, high-temperature treatment at 960 oC/1h, and subcritical treatment at 550 oC/4 h. The microstructure was investigated by OM and SEM; compositions of matrix and carbides were analyzed by EDS. Mechanical behavior of HCWCIs was analyzed by measuring hardness, toughness, abrasive/wear resistance and resistance to repeated impacts. Corrosion behavior was evaluated electrochemically, by linear and Tafel polarization methods in 0,1M NaCl solution. The properties of the modified HCWCIs were compared with the properties of the base unmodified HCWCI alloy (ASTM A532-IIE).

In the paper is investigated the possible to produce briquettes from chips of aluminum alloy and iron powder. Chips of different shapes and sizes are compared, some of which are free of water and oil (cleaned chips), while the rest are left without cleaning (soiled chips). Upsetting and reverse extrusion of the briquettes were studded. The results show that may be accomplished a large extent of deformation of the briquettes when using processes with predominant compressive stresses. Preparation of briquettes of metal chips with good density and quality is of great importance for the efficiency of this process. The results of impact briquetting of grey cast iron chips with rectangular shape and dimensions 15x25x1 mm are presented. Density and quality of briquettes of these chips are compared with those obtained in another work of the authors using cast iron chips with smaller sizes. It has been found that by using a rectangular chips with a large size are produced briquettes with a very low density and poor quality.