ASTM E2448—A Unified Test for Determining SPF Properties

摘要

The determination of the superplastic properties of a material, just like any mechanical property, is highly dependent on the test method, coupon geometry, and analysis of the raw data from the test. Thus the published properties of a material from one source will differ from that of another source unless a common test method is employed. The ASTM E2448 Standard Test Method for Determining the Superplastic Properties of Metallic Sheet Materials has been written to provide a common platform for testing, evaluating, and publishing superplastic properties to a uniform format, useful for both academia and industry. The Boeing Company is now using ASTM 2448 to quantify the superplastic properties of fine grain Ti-6Al-4V alloy, and is specifying it to qualify production material to the Boeing Material Standard BMS7-385. The standard includes specimen geometry and testing conditions, the test machine requirements, and how to analyze the data, including the basic stress vs. strain curve and determination of ‘m’ value.