(60bn) Investigation on the Effect of Cold Drawing Process on Mechanical Properties and Structure of Seamless Steel (Ck60) Tube

Investigation on the effect of cold drawing process on
mechanical properties and structure of seamless steel (Ck60) tube

Professor Dr. Sorush Niknamian Board Member of Weston A
Price Foundation, Washington Dc, USA

E-mail: so.niknamian@gmail.com

Abstract The cold drawing process is one of the precise
metal forming techniques which have attracted attention by many researchers
with respect to the given properties such as potential for improvement of
mechanical properties of the material, achieving of accurate dimensional
tolerances and rise of quality at final surface so that different studies are
conducted on properties of various materials in the course of analysis of its
effect. Using cold drawing and also exertion of special heat treatment cycle in
this investigation, initially the seamless steel tube Ck60 has been produced
and then effect of cold drawing has been assessed on the mechanical properties
and structure of steel. The production process of seamless steel tube includes
two phases of cold drawing which was followed by surface reduction levels 15.1%
and 13.7% respectively. In order to analyze mechanical properties, tensile test
and hardness-testing was used and metallography test was also employed to
observe the structure. The given results indicate that the seamless steel tube
Ck60 produced by means of this production process has ultimate tensile strength
(1021 MPa), yield strength (950 MPa) and elongation (9%). Moreover, the value
of hardness mean was 312 for the final tube in Vickers Hardness Test. The
images taken from optical microscopy also show that the final structure of tube
is uniform and as perlite ferrite.

Keywords: Cold drawing- Seamless tube- Mechanical
properties- Hardness- Structure- Heat treatment