Characterisation of mechanically milled 17-4 PH gas atomized stainless steel powders


Cetinkaya C. , Findik T., Ozbllen S.

Materials and Design, vol.28, no.1, pp.266-271, 2007 (Journal Indexed in SCI Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 28 Issue: 1
  • Publication Date: 2007
  • Doi Number: 10.1016/j.matdes.2005.07.012
  • Title of Journal : Materials and Design
  • Page Numbers: pp.266-271

Abstract

A laboratory scale Szegvari type vertical mechanical alloying (MA)/mechanical milling (MM) attritor for research purposes was designed and constructed at Gazi University. By using this attritor, optimum processing parameters such as milling time, milling speed (rev/min), diameter and the amount of milling balls, milling atmosphere were determined when MM'ing of gas atomized 17-4PH stainless steel powders were carried out. After the milling, powder size analyses and microscopic studies (optical and SEM) were utilized for characterization of the as-received and milled powders. It was observed from the results of the present investigation that for 17-4PH stainless steel (SS) powders, optimum properties were obtained when mechanical milling at Gazi University attritor was carried out at 500 rev/min in Ar gas by using 250 g of 10 mm diameter hardened chromium steel balls. It was also observed that MM time has a profound influence on the characteristics (such as particle size, shape and distribution) of MM'ed 17-4 PH gas atomized SS powders depending on the two competing mechanisms, namely, the rate of welding and the rate of fracturing. © 2005 Elsevier Ltd. All rights reserved.