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This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

A numerical procedure is devised for the thermal analysis of three‐dimensional large truss‐type space structures exposed to solar radiation. Truss members made of an orthotropic material with a closed thin‐walled cross‐section of arbitrary shape are considered. Three‐dimensional thermal effects are taken into account in the analysis. In the proposed method, the governing equations are first put into a weak form. Then the Galerkin finite element method is applied with respect to the axial coordinate of each truss member. The circumferential variation of the temperature is treated by a symbolically‐coded harmonic balance procedure. The interaction between the various truss members is controlled by an iterative scheme. As a numerical example which demonstrates the proposed method, the temperature distribution in a parabolic dish structure is found. The results are compared to those obtained by standard one‐ and two‐dimensional analyses.

Crack tip stresses are used to relate the ability of structures to perform under the influence of cracks and defects. One of the methods to determine three-dimensional crack tip stresses is through the J-T_z method. The J-T_z method has been used extensively to characterize the stresses of cracked geometries that demonstrate positive T-stress but limited in characterizing negative T-stresses. The purpose of this paper is to apply the J-T_z method to characterize a three-dimensional crack tip stress field in a changing crack length from positive to negative T-stress geometries.

Elastic-plastic crack border fields of deep and shallow cracks in tension and bending loads were investigated through a series of three-dimensional finite element (FE) and analytical J-T_z solutions for a range of crack lengths ranging from 0.1⩽a/W⩽0.5 for two thickness extremes of B/(W − a)=1 and 0.05.

Both the FE and the J-T_z approaches showed that the combined in-plane and the out-of-plane constraint loss were differently affected by the T-stress and the out-of-plane size effects when the crack length changed from deep to shallow cracks. The conditions of the J-T_z dominance on the three-dimensional crack front tip were shown to be limited to positive T-stress geometries, and the J-T_z-Q^2D approach can extend the crack border dominance of the three-dimensional deep and shallow bend models along the crack front tip until perturbed by an elastic-plastic corner field.

The paper reports the limitation of the J-T_z approach, which is used to calculate the state of three-dimensional crack tip stresses in power law hardening materials. The results from this paper suggest that the characterization of the three-dimensional crack tip stress in power law hardening materials is still an open issue and requires other suitable solutions to solve the problem.

This paper demonstrates a thorough analysis of a three-dimensional elastic-plastic crack tip fields for geometries that are initially either fully constrained (positive T-stress) or unconstrained (negative T-stress) crack tip fields but, subsequently, the T-stress sign changes due to crack length reduction and specimen thickness increase. The J-T_z stress-based method has been tested and its dominance over the crack tip field is shown to be affected by the combined in-plane and the out-of-plane constraints and the corner field effects.

Presents a review on implementing finite element methods on supercomputers, workstations and PCs and gives main trends in hardware and software developments. An appendix included at the end of the paper presents a bibliography on the subjects retrospectively to 1985 and approximately 1,100 references are listed.

The incremental radial forging process employs several tens or hundreds of incremental local strokes, so that the entire process is difficult to analyze due to large computation time and large computer memory. The objective of this work is to propose a new numerical scheme of the finite element method, automatic expansion of domain (AED), to reduce computation time and computer memory. In the AED scheme, an effective analysis domain in each local forging step is defined and then the domain is automatically expanded in accordance with the repeated process. In order to verify the validity of the criterion for the AED scheme and the applicability of the AED scheme, two‐dimensional incremental plane‐strain forging process is first analyzed using the proposed scheme with various criteria and full domain. In addition, three‐dimensional incremental radial forging process is analyzed to verify the applicability of the proposed scheme to a practical incremental forging process.

The purpose of this paper is to propose a novel mathematical model to present the three-dimensional tolerance of a discrete surface and to carry out an approach to analyze the tolerance of an assembly with a discrete surface structure. A discrete surface is a special structure of a large surface base with several discrete elements mounted on it, one, which is widely used in complex electromechanical products.

The geometric features of discrete surfaces are separated and characterized by small displacement torsors according to the spatial relationship of discrete elements. The torsor cluster model is established to characterize the integral feature variation of a discrete surface by integrating the torsor model. The influence and accumulation of the assembly tolerance of a discrete surface are determined by statistical tolerance analysis based on the unified Jacobian-Torsor method.

The effectiveness and superiority of the proposed model in comprehensive tolerance characterization of discrete surfaces are successfully demonstrated by a case study of a phased array antenna. The tolerance is evidently and intuitively computed and expressed based on the torsor cluster model.

The tolerance analysis method proposed requires much time and high computing performance for the calculation of the statistical simulation.

The torsor cluster model achieves the three-dimensional tolerance representation of the discrete surface. The tolerance analysis method based on this model predicts the accumulation of the tolerance of components before their physical assembly.

This paper proposes the torsor cluster as a novel mathematical model to interpret the tolerance of a discrete surface.

This paper aims to present the designing and investigating various types of impulse blade profiles to find the optimal profile that has better performance than the first or original blade. The studied model is a turbine with an output power below 1 MW and a large pressure ratio up to 20, which is used to gain relatively high specific work output. As a result of its low mass flow rate, the turbine is used under partial-admission conditions. The turbine’s stator is a group of convergence–divergence nozzles that provide supersonic flow.

More than 10 types of two-dimensional blade profiles were designed using the developed preliminary design calculations and numerical analysis. The numerical results are validated using the existing experimental results. Finally, the case with improved performance is introduced as the final optimum case.

It was found that the performance parameters such as efficiency, power and torque are increased by more than 8% in the selected best model, in comparison with the original model. Moreover, the total pressure loss is 12% decreased for the selected model. Finally, the selected profile with superior performance is proposed.

Simultaneous numerical tests are conducted to examine the interaction of different supersonic blade profiles with the partially injected flow to the rotor.

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.