Effect of a Trace Addition of Sn on the Aging Behavior of Al–Mg–Si Alloy with a Different Mg/Si Ratio

In this paper, the effect of trace Sn on the precipitation behavior and mechanical properties of Al–Mg–Si alloys with different Mg/Si ratios aged at 180 °C was investigated using hardness measurements, a room-temperature tensile test, transmission electron microscopy and differential scanning calorimetry. The results shown that Sn reduces the precipitation activation energy, increases the number density of β″ precipitates, and then increased the aging hardenability and mechanical properties of the Al–Mg–Si alloy. However, the positive effect of Sn on the mechanical properties of the Al–Mg–Si alloy drops with the decrease of the Mg/Si ratio of the alloy.

Optimization of Precipitation Phase Type and Mechanical Properties of X2A66 Alloy by Pre-Deformation Treatment

In the present work, the effects of pre-deformation before aging on the precipitation phase and mechanical properties of a new type X2A66 alloy was investigated with the help of the room temperature tensile test, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) methods. The experimental research results prove that reducing the aging temperature or pre-deformation before aging is beneficial to improve the mechanical properties of the alloy. Compared with decreased aging temperature, pre-deformation treatment before aging can significantly improve the mechanical properties of the alloy, and its yield strength (YS), ultimate tensile strength (UTS) and elongation are 593.4Mpa, 610.8Mpa, and 10.7%, respectively.

Microstructure and Mechanical Properties of As-Cast and As-Extruded Mg-Gd-Er-Zn-Zr Alloy

The Microstructure and mechanical properties of as-cast and as-extruded Mg-12Gd-2Er-1Zn-0.6Zr alloy are investigated in the present paper. The microstructure is analyzed by OM, SEM and TEM with SAED, and the mechanical properties are valued by the room temperature tensile test. The result shows that the coarse Mg5(Gd, Er, Zn) phase in the as-cast alloy was broken during hot extrusion process, and it was distributed at the grain boundary along the extrusion direction. The enhancement in mechanical properties of the extruded alloy is mainly ascribed to the refinement of these grains. The sizes of dynamical recrystallized grains are homogeneously, which was about 7 μm. Stacking fault existed in the as-cast alloy, which has a little effect on the dynamic recrystallization because of its tiny thicknesses.

Effect of Cobalt Addition on the Deformation and Recrystallization Textures of Polycrystalline IN713C Nickel Based Superalloy

The aim of this study was to examine the effect of cobalt addition on the deformation and recrystallization behavior. The prepared material was Inconel 713C nickel base superalloy. In order to improve the deformability, the IN713C was modified by cobalt addition with 5 and 10wt%. Mechanical property was determined by room temperature tensile test with the strain rate of 10-3s-1.The recrystallization was performed at 1473K for 300sec followed by oil quenching. The final microstructure becomes homogeneous through cobalt addition. Strength and work hardening rate were decreased during room temperature tensile test. By contrast, elongation was increased. Nucleation site was changed by cobalt addition. It was found that kinetics of recrystallization is dependent of the cobalt addition. The cobalt addition is attributed with ductility and recrystallization behavior and the latter is related to change of deformation behavior.

Study on Direct Annealing Process of Hot-Rolled Plate

To study the transmutation of organization and texture on direct annealing process of hot-rolled plate. Different annealing experiments were done in the lab. The annealed samples are from steel grade of SPHC. To check the organization of the annealed samples by optical microscopy, to measure grain size by Micro-image Analysis & process software. To measure the mechanical properties by the room temperature tensile test. To check AlN by TEM and EDX.To measure texture by texture measuring instrument, and the data was collected on a computer, using two-step calculation of ODF, measured with constant 45° section of graph. When annealing temperature of the samples reaches 875 °C or more, a relatively low strength , high n value, and high r value is received, but if the holding time is longer, grain coarsening occurs at the time,so the annealing temperature is not more than 925°C.When annealing temperature reaches 875 °C, AlN increased slightly, and the texture is not obvious.