An introduction to aluminum Powder Metallurgy (PM) technology - Jessu Joys, United States Metal Powders Inc, USA

Aluminum PM Technology is the process of making press and sintered parts using Aluminum powder blends/alloys, which contains percentages of copper, magnesium, silicon or similar elements.  Aluminum PM Parts can be produced by making minimal changes to the processing conditions of the current ferrous, brass or bronze PM parts.  One of the major advantages of using aluminum powder is its superior compressibility compared to any other powders.  Typical compacting pressure of standard aluminum powder grades range from 10-15 TSI to get to 93% of the theoretical density compared to a ferrous powder part that will require 30-35 TSI to get a density of 80%. The Aluminum powder blends are press-ready and pre-lubricated with sufficient amount of lubricant.  The compacted green parts can be sintered in a conventional production furnace at a low sintering temperature around 600oC (1112oF) and the recommended furnace atmosphere is nitrogen with a dew point near -45oF. Selecting the proper grade from the available Aluminum powder blends should be based on the mechanical property specification of the final parts.  A series of parts with simple to complex geometry are being produced in the industry. Aluminum PM camcaps for the automobile industry are the perfect example of a successful aluminum PM part.  Some of the other parts are the small gear/bearing parts in non-automobile applications.  Many aluminum parts produced by conventional methods are being converted to PM parts as an efficient way to eliminate/minimize the percentage of scrap and to attain improved mechanical properties.  One of the other major concerns about Aluminum PM is its hazardous nature and the millions of PM parts produced globally show that it is as safe as any other PM product as long as it is handled properly.  One of the recent major improvements in aluminum PM technology is the development of ceramic reinforced materials for parts that require higher wear resistance.