Usage of Gray Cast Iron for Hardening of Agricultural Machines’ Soil-Tilling Implement

Abstract

Research of gray cast iron was established to study physical-mechanical properties in microstructure while apply a layer on steel basis of work tool’s soil-tilling. Gray cast iron went through preliminary heat treatment, where gray cast iron hardening with temperature of 750…1050 °C with following water quenching. Research program including: comparison analysis of reference specimen and specimens which were went through heat treatment. Researching material was applied on work tool’s soil-tilling with two methods: arc surfacing and elcetrosparck surfacing. Microstructure of welding layer after arc welding and electrospark welding was studied. Therefore was found out that elecrosparck method gave opportunity to obtain wear resistant layer for a few run, also structure and basis of gray cast iron doesn’t change. Coarse graining doesn’t spot in pad weld, which is beneficial for properties. Measurement of welding layer’s hardness is bigger than base metal and there is no softening of basis. Field tests of hardened products which have shown that to use effectively gray cast iron with heat treatment for hardening, because quality and coating thickness is meeting the requirements of abrasive resistance and there are no spotted significant changes of geometrical dimension for soil-tilling implement.