The Determination Principle And Method Of Strontium In Magnesium-strontium Master Alloy

Magnesium alloys, as the lightest structural materials, are rapidly developed fast in the automotive industry.However, at present the combination property of magnesium alloys is very poor, which can be increased by alloying. Strontium is one of the effective alloying elements. Strontium effectively refines the grain, reduces the micro-porosity, and heightens the creep resistance and heat cracking resistance performance of magnesium alloys. Therefore, the study of the proper addition of strontium in magnesium is hot .The preparation and determination of magnesium-strontium master alloys are very important for the addition of strontium to magnesium alloys in the form of magnesium-strontium master alloys. Researches on magnesium-strontium master alloys and its determination technologies are reported uncommonly. In this dissertation, the determination of strontium in magnesium-strontium alloys has been studied.The air-acetylene Flame Atomic Absorption Spectrometry (FAAS for short) was for first time utilized to determine the Strontium in magnesium alloys. The factor such as the flow of acetylene, burner altitude, the preparation of the sample , the inference of matrix and coexistence elements, have been investigated. The method is convenient and rapid with good precision and accuracy.Moreover, microstuctures and phases of Mg-Sr alloys, were studied by Optics Microscope(OM for short ),Scanning Electron Microscope(SEM for short),X-ray Diffraction (XRD for short),etc. The results are shown that:â‘ the morphology of magnesium-strontium master alloy was network structure ,and the laminary eutectic morphology distributed at the grain boundary or in the interdendritic regions.â‘¡The distribution of strontium is segregated by micro-area chemical analysis. The content of strontium inα-Mg phase is little and the content of strontium in the laminary eutectic is 11.84%.â‘¢The quantitative analysis for metallographic phase adopted the image analysis software designed by myself, which can inversed the content of strontium in magnesium-strontium master alloy with the distribution of strontium. The calculation of inversion formula and the theoretical value have some relationship, which are showed by mathematical model. The mathematical model is followed: ,β₁ andβ₀ are0.99 and 0.70,respectively by the...