Two-layer metallic sheets have wide applications in aerospace, marine, automotive and domestic industries due to their superlative characteristics. In this paper, the formability of two-layer sheet is investigated through analytical, experimental and numerical approaches. An analytical model is developed based on Marciniak-Kuczynski method associated Hill’s non-quadratic yield criterion. Formin...

The paper deals with devising the combination of fuzzy inference systems (FIS) and neural networks called the adaptive network fuzzy inference system (ANFIS) to determine the forming limit diagram (FLD). In this paper, FLDs are determined experimentally for two grades of low carbon steel sheets using out-of-plane (dome) formability test. The effect of different parameters such as work hardening...

In this research, Forming Limit Diagrams for supertension sheet metals which are using in automobile industry have been obtained. The exerted strains to sheet metals have been measured with four different methods and the errors of each method have also been represented. These methods have been compared with together and the most efficient and economic way of extracting of the exerted strains to...

Sheet metal forming boundaries are established using the limit diagram (FLD). The Nakajima and Marciniak tests, which based on stretching a material punch, most commonly used methods for determining FLD or fracture (FFLD). results usually evaluated by calculating local strain, strain rates, specimen thickness reduction strain. When amount of experimental is insufficient, miniaturization testing...

We analyze an array of linearly extended monodomain dipoles forming square and kagome lattices. We find that its phase diagram contains two distinct finite-entropy kagome ice regimes—one disordered, one algebraic—as well as a low-temperature ordered phase. In the limit of the islands almost touching, we find a staircase of corresponding entropy plateaux, which is analytically captured by a theo...

Nowadays, with extending applications of bi-layer metallic sheets in different industrial sectors, accurate specification of each layer is very prominent to achieve desired properties. In order to predict behavior of sheets under different forming modes and determining rupture limit and necking, the concept of Forming Limit Diagram (FLD) is used. Optimization problem with objective functions an...

This paper presents a comparison between a number of different failure prediction methods for superplastic forming processes. Attention is limited here to superplastic forming of Ti-6Al-4V at 927C. The failure prediction methods considered include the flow localisation factor approach, forming limit curves based on void growth models, such as the Rice and Tracey model and the Cocks and Ashby mo...