Comparison between extrusion surface densification and rolling surface densification
DING Xia1，PENG Jingguang2，CHEN Di2
1.School of Mechanical and Automotive Engineering，Shanghai University Of Engineering Science，Shanghai
201620，China； 2.School of Materials Science and Engineering，Shanghai University，Shanghai 200436，China
Abstract：Selective surface densification process mainly includes extrusion densification and rolling densification.
Based on the production of surface densified parts, this paper compared and analyzed the differences between extrusion
densification and rolling densification from the aspect of parts performance testing. The experimental results
show that a uniform surface dense layer can be formed at the tooth profile of the parts prepared by the two processes,
and the surface strength and hardness of the parts are greatly improved. Extrusion densification process will
lead to flanging on the end face of sintered parts, which is easy to cause appearance quality problems of subsequent
sintered parts, while rolling densification process will not produce similar appearance quality problems. In the extrusion
densification process, the extrusion feed depends on the die size, which can not be adjusted at will, and it
will change with the wear of the radial size of the die. In the rolling densification process, the rolling feed can be
quickly adjusted by adjusting the distance between the central axis of the two roller dies, and the required surface
densification layer can be prepared. Therefore, rolling densification is better than extrusion densification.
2022, Vol. 32 
