| Abstract: | Woehler tests on component‐like specimen of MRI 153M The alloy MRI 153M shall increase the application of Magnesium because of its comparable properties to AZ 91 but better static strength properties at temperatures up to 150° C. Constant amplitude tests were performed with component‐like specimen under variable environment conditions. The modified parameters were the notch radius (r=3 mm or r=12 mm), the stress ratio (R=0 or R=‐1), the surrounding temperature (room temperature, 120° C or 150° C) and the cast skin. At room temperature the Woehler curves of MRI 153M trend to higher cycles to crack initiation than AZ 91 and AM 60. If the local stresses are compared, the specimen with r=12 mm show earlier crack initiation because of the influence of size. The decrease of fatigue under higher temperature is about one scatter range and can be valuated as moderate. Between 120° C and 150° C the fatigue values do not show any significant differences. The removal of the cast skin has no influence on the lifetime of the component. |
