Microstructural change and precipitation hardening in melt–spun Mg–X–Ca alloys

Precipitation Hardening of Metal Alloys

Precipitation hardening, or age hardening, provides one of the most widely used mechanisms for the strengthening of metal alloys. The fundamental understanding and basis for this technique was established in early work at the U. S. Bureau of Standards on an alloy known as Duralumin [1,2]. Duralumin is an aluminum alloy containing copper and magnesium with small amounts of iron and silicon. In a...

Precipitation hardening in dilute Al–Zr alloys

The aim of this study was to investigate the effect of solute content (hipoperitectic Al–0.22 wt.%Zr and hiperperitectic Al–0.32 wt.%Zr) on the precipitation hardening and microstructural evolution of dilute Al–Zr alloys isothermally aged. The materials were conventionally cast in a muffle furnace, solidified in a water-cooled Cu mold and subsequently heat-treated at the temperature of 650 K (3...

Precipitation Hardening of Al–Si–Mg Alloys

Modelling of Precipitation Hardening in Casting Aluminium Alloys

Precipitation hardening, because it involves the hardening of the material over a prolonged time, is also called age hardening, or ageing. By the appropriate heat treatment of precipitation hardening, the strength or hardness of some heat-treatable aluminium alloys can be enhanced by the formation of nano-meter sized second-phase precipitated particles within the original phase matrix. The fine...

Precipitates and intermetallic phases in precipitation hardening Al–Cu–Mg–(Li) based alloys

The present study contains a critical review of work on the formation of precipitates and intermetallic phases in dilute precipitation hardening Al–Cu–Mg based alloys with and without Li additions. Although many suggestions for the existence of pre-precipitates in Al–Cu–Mg alloys with a Cu/Mg atomic ratio close to 1 have been made, a critical review reveals that evidence exists for only two tru...