Actual Problems in Machine Building 2020 Vol. 7 No. 1-2

Актуальные проблемы в машиностроении. Том 7. № 1-2. 2020 Материаловедение в машиностроении ____________________________________________________________________ 121 РOSSIBILITY OF USING WHITE UNALLOYED CAST IRON AS INSTRUMENTAL MATERIAL Afanasyev V.K. 1 , D.Sc. (Engineering), Professor, e-mail: in_afanaseva@mail.ru Popova M.V. 1 , D.Sc. (Engineering), Professor, e-mail: m.popova@rdtc.ru Dolgova S.V. 1 , Junior Researcher, e-mail: sv_dolgov@mail.ru Zhibinova I.A. 2 , Ph.D. (Engineering), Associate Professor, e-mail: irina.zhibinova@mail.ru Chernysh A.P. 3 , Ph.D. (Engineering), Associate Professor, e-mail: tmrm@mail.ru 1 Siberian State Industrial University, 42 Kirov st., Novokuznetsk, 654007, Russian Federation 2 Kemerovo State University, Novokuznetsk Branch, 23 Tsiolkovsky st., Novokuznetsk, 654041, Russian Federation 3 Kemerovo Research Institute of Agriculture, Branch of Siberian Federal Scientific Centre of Agro-BioTechnologies of the RAS, 47 Tsentral'naya st., Novostroika village, 650510, Russian Federation Abstract This article presents the results of studies of the structure and properties of the new instrumental material - unalloyed cast iron without graphite release. In order to obtain such cast iron, the liquid blast furnace cast iron was thermocyclically treated. By means of thermocyclic treatment it is possible to suppress the graphitization process and obtain white cast iron with the structure of ledeburite. It is shown that the developed not alloyed white cast iron in a cast state has high hardness 450-500 HB (50 HRC) and strength σ в = 450-500 MPa. Studies were carried out on influence of different modes of thermal and thermocyclic treatment in the range of 80-1200 ° C on hardness of cast iron without graphite release. It has been found that the strength and hardness of unalloyed white cast iron can be increased after heat treatment. Influence of various quenching media and heating time for quenching is studied. It is shown that after quenching from 900 ° C in boiling water cutters from white unalloyed cast iron have hardness 65-67 HRC, which allows to treat wood, particle boards, low-carbon steels. Keywords White unalloyed cast iron, cutting instrument, microstructure, hardness, graphite, ledeburite, thermal treatment.