Microstructure Evolution and Mechanical Properties of the 2195 Al-Li Alloy via Different Annealing and Ramp Heating-Up Treatments

In this paper, the microstructure evolution of the 2195 Al-Li alloy under different isothermal annealing schedules and ramp heating-up heat treatments prior to solution heat treatment and the tensile properties of the aging alloy were investigated. The grain structure characteristics of the aging alloy could be influenced by the change of different heat treatment schedules prior to the solution heat treatment. Meanwhile, the mechanical properties of the aging alloy including strength, heterogeneity, and anisotropy were closely related to the grain structure characteristics. There were evident differences in the mechanical properties of aging samples, attributed to the mutual effect of grain structure evolution and texture change. Annealing at a lower temperature (300–350 °C) resulted in the growth of the grain size and the aspect ratio as well as the decrease of the deformation texture components, related to the decline of the strength and the heterogeneity. While grains refined and the deformation texture components increased as the annealing temperature rose (350–400 °C), the strength along the transverse direction decreased, and the heterogeneity increased. Fibrous and overall texture components significantly strengthened in the grain structure of aging samples treated with the low heating-up rate, resulting in a higher strength in the longitudinal direction.

STUDY OF PRECIPITATION KINETICS OF AN AL-MG-SI ALLOY USING DIFFERENTIAL SCANNING CALORIMETRY

<p class="AMSmaintext">This work has been carried out by differential scanning calorimetric (DSC) to study the precipitation kinetics in quenched and natural aging Al-Mg-Si alloy. DSC curves showed exothermic and endothermic peaks corresponding to the precipitation and the dissolution processes. The activation energy of the precipitation process has been calculated using Kissinger model. The results obtained showed a change in the activation energy values, the activation energy for the β″ and β determined for natural aging alloy were higher than that in the quenched alloy. </p>

Effect of Aging Time to the Commercial Aluminum Alloy Modified with Zirconium Addition

The influence of heat treatment condition with addition of zirconium on the some properties of aluminum alloy has been investigated. The composition of aluminum alloy cast produce from this research was supplied from the foundry. The cast alloys were given a solutionizing treatment at 520°C followed by artificial aging at 175°C for a different period of time up to 10 hours. Hardness of heat treated aluminum alloy then were determined by comparing to the as cast and natural aging alloy. The addition of zirconium will improve the properties of the alloy in term of hardness and conductivity. Grain size of alloy has no significant effect when aging time increased together with zirconium addition.

Compressive Properties of AM60 Magnesium Alloy by High-Pressure Solution and Subsequent Atmospheric-Pressure Aging Treatment

As-cast AM60 magnesium alloy was solid dissolved with exercising different pressures (atmospheric-pressure, 3, 4 and 5 Gpa) to it and subsequently aged for 10 h at 200 °C under atmospheric-pressure. The aging alloys were characterized by optical microscope, and their compressive properties were investigated by a Gleeble-3500 hot-stimulation machine. The results show that, compared with exercising atmospheric-pressure during solution treatment, exercising high-pressure during this process causes that the α-Mg grains of the subsequent aging alloy are more fine and uniform, while the β-Mg17Al12 phases transform into fine particles and aggregate to form gobbets or strips. With increasing the pressure gradually, the compressive strength of the aging alloy increases up to 4 Gpa and then decreases, while the maximum plastic strain decreases up to 4 Gpa and then increases.

Microstructure of AM60 Magnesium Alloy by High-Pressure Solution and Subsequent Atmospheric-Pressure Aging Treatment

As-cast AM60 magnesium alloy was solid dissolved with exercising different pressures (atmospheric-pressure, 3, 4 and 5 Gpa) to it and subsequently aged under atmospheric pressure. The microstructure of the products was characterized by optical microscope and X-ray diffraction. The results show that, compared with exercising atmospheric-pressure during solution treatment, exercising high-pressure during this process causes that the α-Mg grains of the subsequent aging alloy are more fine and uniform, while the β-Mg17Al12 phases transform into fine particles and aggregate to form gobbets or strips. In addition, increasing the exercising pressure promotes the precipitation of the β-Mg17Al12 phases of the aging alloy.

INCONEL ALLOY 783

Inconel Alloy 783 is an oxidation resistant, low expansion, nickel-cobalt-iron alloy with other additions. The alloy is a three-phase aging alloy that is of interest for close clearance control components in the aerospace arena. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and shear strength. It also includes information on corrosion resistance as well as forming, heat treating, and machining. Filing Code: CO-95. Producer or source: Special Metals Corporation. Originally published January 1995, revised February 2004.