The purpose of this lab is to create two material samples through the process of powder metallurgy. After these samples have been manufactured completely through this process then they are evaluated under a microscope. One sample was sintered, and the other one was in its original compacted state for a comparison of how sintering affected the properties of the sample material. Theory:
There are many different forms of Powder Metallurgy, but die pressing is the dominant technology for the initial forming of the products, in terms of both tonnage quantities and production capacity. This technology involves a simple production cycle, including: 1. Filling a die cavity with a known volume of powder stock. 2. Compaction of the powder within the die with punches to form the compact. 3. Ejection of the compact from the die
4. Removal of the compact from the upper face of the die using the fill shoe in the fill stage of the next cycle. Using this process, you must consider multiple design features. You must be able to physically remove the part from the die after compacted. The part should not have a wall thickness less than 0.080”, not exceed the maximum surface area of twenty square inches. Another very important feature is to avoid sharp corners as much as possible in design; these are areas that can easily have non-fills. Powder Metallurgy is not a new concept by any means. This has been around, in crude examples, since as early as 3000 B.C. when Egypt was using this to create sintered ceramics and jewelry. However, mass manufacturing of P/M products did not begin until the mid-to-late 19th century. After the powder has been compacted, a process called Sintering has to be completed. This Sintering is the process of taking metal in the form of powder and transforming it, using heat to create the bonding needed between porous aggregate particles, to a solid piece of the desired metal. Though sintering is...