Die-Wall Lube Technical Publications
91. Engineered Approach to High Density Forming using Internal and External Lubricants: The drive to obtain higher densities, strength and dynamic properties in PM has prompted the development of methods, including Double Press / Double Sinter, Copper Infiltration, Warm Compaction etc., to achieve these goals. One of the contributing factors influencing higher densities is the addition of lubricant to the premix. With advances in lubricant technology and binder-treated premixes it is possible to achieve higher density parts, with reduction of internal lubricant and die wall lubrication This study combines the effects of using a balance of internal and external lubrication to improve the properties of PM materials.
40. Enhanced Green Strength Material System for Ferrous and Stainless PM Processing: Strength limitations of green powder metallurgy compacts often present fabricators with processing problems. Increased part complexity, process automation and the need for reduced green scrap requires the PM compact to attain higher green strength. Currently, several limitations restrict the ability to increase green strength in PM compacts. Powder characteristics, such as particle size distribution and morphology, compressibility and common lubricant systems, all pose limitations on the compact green strength. Enhanced material systems improve the green strength of ferrous-based PM parts by a minimum of 100% relative to compacts containing admixed lubricant. Process advantages, specific test results, and side effects of high green strength systems will be discussed.