Cavitation toughness of in situ nitrided Al-AlN composite sintered material

The cavitation toughness of sintered Al-AlN composite material produced by the direct nitriding process has been examined compared with the composite aluminium alloy produced by the conventional premixing process. Based on the experimental results of the weight loss of the specimen during the cavitation test and changes in AlN intensities of XRD analysis, the directly nitrided composite shows superior properties to the conventional one because dispersed AlN hard particles have a strong and metallurgical bonding to the matrix of the composite, and they improve its cavitation resistance. The toughness of the Al-AlN composite remarkably increases with the increase of the in situ reacted AlN content.