2003 Volume 89 Issue 5 Pages 593-600
Piercer roll in the pipe manufacturing mills requests the wear resistance and bite efficiency. Usually, low carbon alloyed cast steels are applied to the piercer roll, but have low wear resistance. In order to improve the wear resistance of piecer roll, three tests samples with high carbon content and low hardness are investigated. The most suitable carbon level was determined by using the high temperature wear simulator. The main results obtained are as follows; (1) Microstructure of new piecier roll material consists of ferrite and spheroidal carbide. (2) The carbides except spheroidal carbide cause to heat cracks by thermal shocks to decrease wear resistance and resistance to surface roughness. (3) In case of high temperature wear testing, the micro-structure of matrix consisting much of ferrite structure shows the good wear resistance than the matrix of pearlite structure contained. (4) Ferrite structure is worn by abrasion mechanism and pearlite causes to fatigue cracking and pealing off. (5) The excellent wear resistance of low hardness roll consists of the spheroidal carbide and ferrite, which is gripping carbide and is worn keeping the effective surface roughness.