Abstract: Methods of enhancing mechanical properties of aluminum alloy high pressure die castings are disclosed herein. An aluminum alloy composition forming a casting comprises, by weight of the composition, at least one of a magnesium concentration greater than about 0.2%, a copper concentration greater than about 1.5%, a silicon concentration greater than about 0.5%, and a zinc concentration greater than about 0.3%. After solidification, a casting is cooled to a quenching temperature between about 300° C. and about 500° C. Upon attainment of the quenching temperature, the casting is removed from the die and immediately quenched in a quench media. Following quenching, the casting is pre-aged at a reduced temperature between about room temperature and about 100° C. Thereafter, the casting is aged via at least one substantially isothermal aging at one or more elevated temperatures between about 150° C. and about 240° C.

Abstract: Methods and technologies to maximize the aging response and the mechanical properties of aluminum alloys are provided. In one embodiment, the aging process for the slowly-quenched aluminum alloys includes, but is not limited to, at least a two-stage solution treatment and a two-stage aging hardening. In the solution treatment, the components are first heat treated at an initial solution treatment temperature and then gradually heated up to about 5° C. to about 30° C. above the initial solution treatment temperature for the material. For the aging treatment, the castings/components are first aged at a lower temperature followed by a higher temperature for the subsequent aging stages. The temperature increase during solution treatment and/or aging can be in steps, in a continuous manner, or combinations thereof. Another embodiment includes a two stage aging process in which there is a non-isothermal aging step.

Abstract: A system for evaluating a manufacturability of a casting design. The system includes at least one of a geometry analyzer, a casting evaluation tool, a residual stress evaluation tool, and a machining evaluation tool. The geometry analyzer analyzes a geometric design of the casting design to determine its geometric design-ability, the casting evaluation tool evaluates the casting design to determine its cast-ability, the residual stress evaluation tool evaluates the casting design to determine its heat treat-ability, and the machining evaluation tool evaluates the casting design to determine a machine-ability of the casting design. If the casting design is determined as not geometrically design-able, not cast-able, not heat treat-able, or not machine-able by the geometry analyzer, the casting evaluation tool, the residual stress evaluation tool, or the machining evaluation tool, respectively, then modifications to the casting design are recommended to optimize the casting design for manufacturing.

Abstract: A casting design system (101) is provided which comprises (a) a database (115) which contains casting design data and rules, (b) a user interface (109), in communication with the database, which accepts as input a product design (103) that is to be cast by a casting process, and (c) an inference engine (111) which is adapted to generate casting designs (114) from the input product design by searching the database and retrieving data therefrom.

Abstract: A system and method for predicting fatigue life in metal alloys for very high cycle fatigue applications. The system and method are especially useful for cast metal alloys, such as cast aluminum alloys, where a fatigue endurance limit is either non-existent or hard to discern. Fatigue properties, such as fatigue strength in the very high cycle fatigue region, are based on a modified random fatigue limit model, where the very high cycle fatigue strength and infinite life fatigue strength are refined to take into consideration the sizes of the discontinuities and microstructure constituents since the fatigue life scatter depends upon the presence of discontinuities and microstructure constituents. The sizes of the discontinuities and microstructure constituents that can initiate fatigue cracks can be determined with extreme value statistics, then input to the modified random fatigue limit model.

Abstract: A method of providing solution heat treatment to an aluminum alloy. A non-isothermal process is used to provide a faster heat treatment cycle time while maintaining or further improving the alloy mechanical properties after subsequent aging hardening. The process includes establishing a temperature inside a processing vessel that is greater than a soaking temperature but less than a liquidus temperature of the alloy, rapidly heating the alloy to the soaking temperature in a first heating operation, reducing the temperature inside of the processing vessel to the soaking temperature, then heating the alloy to a temperature above the soaking temperature through a gradually increasing temperature in a second heating operation. Protocols for the improved solution heat treatment may be based on one or more of computational thermodynamics, dissolution kinetics and coarsening kinetics.

Abstract: Methods and systems of predicting fatigue life in aluminum castings that combines extreme values of both casting flaws and microstructures with multiscale life models. The multiscale life models account for differing fatigue crack initiation based on the size scale of the defect and microstructure features, including provisions for generally millimeter scale casting flaws, generally micrometer scale second phase particles by cracking or debonding, or submicrometer scale dislocation interactions with precipitates which form persistent slip bands. In the presence of casting flaws, the fatigue initiation life is negligible and the total fatigue life is spent in propagation of a fatigue crack from such flaws. In the absence of casting flaws, however, the total fatigue life is spent in both crack initiation and propagation, except for the case where fatigue cracks initiate from large second phase particles in a coarse microstructure.

Abstract: Methods and systems of predicting fatigue life in aluminum castings that combines extreme values of both casting flaws and microstructures with multiscale life models. The multiscale life models account for differing fatigue crack initiation based on the size scale of the defect and microstructure features, including provisions for generally millimeter scale casting flaws, generally micrometer scale second phase particles by cracking or debonding, or submicrometer scale dislocation interactions with precipitates which form persistent slip bands. In the presence of casting flaws, the fatigue initiation life is negligible and the total fatigue life is spent in propagation of a fatigue crack from such flaws. In the absence of casting flaws, however, the total fatigue life is spent in both crack initiation and propagation, except for the case where fatigue cracks initiate from large second phase particles in a coarse microstructure.

Abstract: Embodiments of a method for non-isothermally aging an aluminum alloy are provided. The method comprises heating an aluminum alloy at a first ramp-up rate to a maximum temperature below a precipitate solvus value, cooling the alloy at a first cooling rate sufficient to produce a maximum number of primary precipitates, cooling at a second cooling rate until a minimum temperature is reached wherein the growth rate of primary precipitates is equal to or substantially zero, and heating the alloy at a second ramp-up rate to a temperature sufficient to produce a maximum number of secondary precipitates.

Abstract: A casting design system (101) is provided which comprises (a) a database (115) which contains casting design data and rules, (b) a user interface (109), in communication with the database, which accepts as input a product design (103) that is to be cast by a casting process, and (c) an inference engine (111) which is adapted to generate casting designs (114) from the input product design by searching the database and retrieving data therefrom.