The Suitability of Analytical and Numerical Methods for Developing Clinching Processes with Thick Sheet Metal

At present, the use of clinching is mainly restricted to thin sheet metal. Here the joining technology is used for assemblies in mass production due to its great coast efficiency. However, the branches of industry working with thick sheet metal (utility and rail vehicle engineering, shipbuilding and general structural steel engineering) represent a major potential for using clinching technology. Unfortunately, the suitability of clinching for connecting jobs with substantially greater sheet metal thicknesses has neither been sufficiently investigated, nor are there suitable toolsets among system manufacturers that are adapted to the larger overall sheet metal thicknesses. Instead, the state-of-the-art for ascertaining tools for larger sheet metal thicknesses and point dimensions is trial and error accepting the high costs caused by producing a large number of tools and experiments. This paper demonstrates some analytical approaches to this problem and how suitable they are to describing the process of clinching in comparison to the potential of calculation with FEA.

Press Forging Forming of Stepped Holes in Thick Sheet Metal

Press forging forming of thick sheet metal is a combined extrusion process, which is put forward in the presently study. A new technological scheme for a two-step press forging of stepped holes in a thick metal sheet was proposed. Finite element analysis on the two-step process is carried out by using DEFORM-3D. Distributions of effective strain and effective stress were obtained. The study showed that the process not only can form the stepped holes, but also can increase the surface quality and strength of stepped holes in sheet metal parts, According to the numerical simulations process parameter, an experimental die was designed, the simulation results were in good agreement with the experimental data.

Study on a New Technological Scheme for Cold Press Forging Forming of Step Holes in Thick Sheet Metal

An new technological scheme for a two-step cold press forging of step holes in a thick metal sheet was proposed . Finite element analysis on the two-step process is carried out by using DEFORM-3D. Velocity shade contours are obtained. The study shows that the technique can form step holes in thick sheet metal and increase their strength, According to the numerical simulation’s process parameter, an experimental die is designed, the FEA results are in good agreement with the experimental data.

Laser Cutting of Thick Sheet Metal: Surface Plasma Characteristics and Cutting Quality Assessment

The quality laser cutting of thick sheet metals is demanding due to requirements of high precision, lost cost, and short processing time. However, the surface plasma is formed during the cutting process to influence the end product quality. The surface plasma is transiently hot and lowers the resulting cutting quality via increasing thermal erosions from the cut edge edges. In the present study, the surface plasma characteristics are examined using the Langmuir probe. Electron temperature and electron number density are determined in the surface plasma. The cutting quality is, then, related to the plasma characteristics. Scanning Electron Microscopy (SEM) is carried out to examine the microstructural changes at the cut edges. It is found that cutting quality improves at a particular assisting gas pressure; in which case, the influence of surface plasma on the cutting process becomes the minimum.

High Performance Active Elements for Agricultural Machines Made of Ultra High-Strength Steels

This article will highlight various aspects of the production process of high performance active elements made of ultra high-strength steels. Focus is put on the processing of thick sheet metal regarding hot forming by means of punching, embossing, and forging processes as well as on thermo-mechanical treatment. Due to the material thickness of the semi-finished parts/blanks used and owing to the high strength of the materials (Rm > 2600 MPa) current production techniques and parameters from the field of thin sheet metal can only be limitedly be transferred and have therefore been specially investigated for this application.

Influences of Material Thickness on Hole-Flange Forming Limitation

In recent years, the hole-flanged components are not only fabricated for a thin sheet metal but they are also increasingly manufactured for a thick sheet metal especially in the automotive industry. However, most of the past researches have been studied the hole-flanging of thin sheet metal. In this study, the influences of material thickness were investigated using the finite element method (FEM) and laboratory experiments. Based on the stress distribution analysis, as the material thickness increased and the hole-flange forming ratio decreased, the effects of bending feature and the material stretching increased which resulted in the easy crack formation. The relationship between material thickness and hole-flange forming limitation was also investigated. In addition, the poor flatness on flange edge increased as the material thickness increased. The FEM simulation results showed the good agreement with the experimental results.