Characterization of Superplastic Materials by Results of Free Bulging Tests

Abstract

Determination of material constants describing its behavior during superplastic gas forming is the main subject of this study. The main feature of free bulging tests is the stress-strain conditions which are very similar to ones occurring in the most of gas forming processes. On the other hand, the interpretation of the results of such tests is a complicated procedure. The paper presents a simple technique for the characterization of materials superplasticity by free bulging tests, which is based on inverse analysis. The main idea of this technique is a semianalytical solution of the direct problem instead of finite element simulation which allows one to reduce the calculation time significantly. At the same time the results this simplified solution are accurate enough to obtain realistic material constants.

An Accurate Constitutive Model for AZ31B Magnesium Alloy during Superplastic Forming

“…Accurate constitutive material models are essential for the realistic simulation of the SPF process. Many established models found in the literature are identified as phenomenological material models [6][7][8][9][10][16][17][18][19][20][21]. These are viscoplastic models that represent the macroscopic behavior of deformation, usually at a constant forming temperature.…”

“…They reflect mainly the relationship between the effective flow stress and the effective strain and strain rate. The constants in these models are fitted using uniaxial tensile [10] or bulge forming experimental data [9,20,21].…”

Mathematical modeling of making mechanical engineering products based on an information model

“…Papers [5,6,7,13] propose comprehensive manufacturability analysis for a specific set of structural elements contained in the information model; it is suggested such analysis should be based on operation, tooling, and equipment data. This takes into account not only elements obtained by generating the elements of the entire part, but also such elements that were obtained early in design.…”

Identifying the objects in the structure of an e-model by means of identified formal parameters in the design and engineering environment

“…The diversity of technical literature and the recommendations featured in the mechanical engineering design analysis [2] contain the basic information about the structure, the composition, and the characteristics of individual parameters used in the analysis. As of today, when designing a product in CAD/CAM/CAE/PDM systems, it is optimal to analyze the structure of a product in early production, i.e.…”

“…to find the pairing surfaces and select boundary linkages by means of production rules. First-level rules are generated in stages [2].…”