Endurance Tests of Aluminum and Magnesium Casting Alloys Contain-ing Various Degrees of Dispersed Discontinuities

摘要

In this investigation, fatigue strengths for porosity degreesnNumbers 1 through U for aluminum casting alloy AL-355 in the solution treated and aged (T6) condition were determined. Minimum porosity is exhibited by degree Number 1; increasing porosity is in the direction of the higher numbered degrees. Based on the rising order of porosity and the fatigue strength taken as the stress corresponding to "the "fatiguenlife at 10,000,000 cycles, it was found that as porosity increased, thenfatigue strength decreased from a maximum of 12,000 psi for degree Number to a minimum of 9,000 psi for degree Number 4.