Vacuum Inert Gas Atomisation of Cr-Mn-Ni Austenitic Steel Alloys
The Cr-Mn-Ni austenitic steel cast alloys containing 16 wt.-% chromium, 7 wt.-% manganese and 3 to 9 wt.-% nickel are used as matrix material to manufacture TRIP-Matrix-Composite containing MgO partially stabilised ZrO2ceramics. In the present work, these steel master alloys were atomised via a vacuum inert gas atomisation to provide fine grain sized metal powders for the assembling of TRIP-Matrix-Composite. The atomised steel powders where characterised according to their chemical composition and the d50mass median particle size determined by a laser diffraction analyses. The surface tension of the liquid steel alloys was experimentally investigated using the maximum bubble pressure (MBP) method. The reference austenitic steel alloy (AISI 304) has the highest surface tension and the highest mass median particle size compared to the Cr-Mn-Ni steel alloys, where d50values are lower due to lower surface tension values. Finally, it is concluded from the present investigation, that the d50size of the atomised steel powders decreases by a decrease of surface tension values for the liquid steel alloys.