Density and Strength Improvement of Sintered 316L Stainless Steel
Nattaya T osangthum*, Ornmanee Coovattanachai, R ungtip Krataitong, Monnapas Morak otjinda, Anan Da* Author for corresponding; e-mail address: nattayt@mtec.or.th
Volume: Vol.33 No.1 (JANUARY 2006)
Research Article
DOI:
Received: 14 June 2005, Revised: -, Accepted: 23 September 2005, Published: -
Citation: Osangthum N.T., Coovattanachai O., Krataitong R.U., Otjinda M.M. and Da A., Density and Strength Improvement of Sintered 316L Stainless Steel, Chiang Mai Journal of Science, 2006; 33(1): 53-66.
Abstract
Admixing of Ni powder was found to improve some mechanical properties of sintered 316L stainless steel. However, Ni powder addition is not economically feasible due to its high cost. A metal powder, designated as PMTEC1, was employed as an alternative admixing powder for performance improvement of the sintered 316L stainless steel. In this investigation, 316L, 316L+6wt.%Ni and 316L+6wt.%PMTEC1 powders, were processed using a ’press and sinter’ method. Properties of the sintered 316L+6wt.%Ni and 316L+6wt.%PMTEC1 alloys were compared to the sintered 316L stainless steel. Sintering was carried out in different atmosphere compositions. It was found that the factors, such as N2 content in the atmosphere, Ni and PMTEC1, showed some effects on some properties. Particularly, addition of the PMTEC1 significantly increased sintered density, yield strength and hardness with severely sacrificed elongation. The PMTEC1 powder caused grain growth, no matter the sintering atmosphere compositions employed. Nitrogen content in the atmosphere caused formation of nitride. The presence of PMTEC1 not only accelerated grain growth, but also activated nitride eutectoid formation.