2015
14-15#06 NDT & Microstructure Correlations to Gray Iron Aging
Principal Investigator: Greg Miskinis, Waupaca Foundry, Inc.
Steering Committee Chair: Matthew Meyer, Kohler Co.
Gray iron cast components are well known to age or “cure” after casting, resulting in strength and resonant frequency (RF) increases over time. Previous research has shown this aging effect to be logarithmic with most of the effect (70% or so) coming in the first 15 days after casting. There are multiple theories, however, regarding how best to account for and benefit from this aging process. One benefit may be a reduction in machining tool wear. Improved tool life has been found to occur in aged castings in multiple machining trials over the years.
This study worked to determine the optimal balance of aging, part and NVH (noise, vibration, harshness) performance, and also secondary operations versus processing limitations and inventory requirements or work in process (WIP) costs.
Library Paper Number: 16-017
2014
13-14 #01 Development of Ultra-High Strength Light Weight Al-Si Alloys
Principal Investigator: Mohammad Shamsuzzoha, University of Alabama, Tuscaloosa
Steering Committee Chair: David Weiss, Eck Industries
Typical hypo- and hyper-eutectic alloys grown by impurity-modified conventional casting exhibit a microstructure comprising of primary Si that assumes sizes on the order of 10-4 m and eutectic silicon with a rather course fibrous morphology of sizes on the order of 10-6 m. These properties of the microstructure have not provided ultra-high strength and fracture toughness for such as cast alloys. Recently a new procedure based upon the concept of the solubility of Barium (Ba) in the silicon phase has demonstrated that a hypereutectic Al-17wt%-Si alloy can be produced without a primary Si phase being present.
Library Paper Number: 15-087