Jacek Mucha

Joining the car-body sheets using clinching process with various thickness and mechanical property arrangements

The clinching joints are more and more used when assembling sheet plate elements, especially in an automotive industry. The clinching joint is created by local stamping of joined sheets without heat effect on the material structure. This paper presents the analysis of effect of the thickness layout change and sheet type and die on the joint strength change. The shearing strength analysis of created joints has been presented. The shearing test results of the clinching joint have been compared with results achieved for spot welding joints of similar joint diameter.

The Experimental Analysis of Forming and Strength of Clinch Riveting Sheet Metal Joint Made of Different Materials

The paper presents the pressed joint technology using forming process with or without additional fastener. The capabilities for increasing the load-carrying ability of mechanical joints by applying special rivets and dies were presented. The experimental research focused on joining steel sheet metal made of different materials. The joint forming was performed with the solid round die and rectangular split die for riveted joint forming. The load-carrying ability of joints was evaluated by measuring the maximum load force in the shearing test in the tensile testing machine. The effect of joint forming process on joined material strain was compared by measuring the microhardness of the joints.

CLINCHRIVET AS AN ALTERNATIVE METHOD TO RESISTANCE SPOT WELDING

Abstract Various materials are used in car body production which are not always possible to join by conventional joining methods such as resistance spot welding. Therefore ClinchRivet method seem to be possible alternative. The paper deals with evaluation of properties of the joints made by mechanical joining method - ClinchRivet. The joint is made with the using of a special rivet, which is pushed into the joined materials by the flat punch. Following materials were used for joining of this method: DX51D+Z and H220PD steel sheets. The tensile test for observing the carrying capacities and metallographicall analysis were used for the evaluation of joint properties. Some results of the tests of ClinchRivet joints were compared to the properties of the joints made by resistance spot welding.

FEM Analysis of Clinching Tool Load in a Joint of Dual-Phase Steels

The clinching tool with a die of 5 mm diameter with a specially formed gap and a punch of 3.6 mm diameter were used for mechanical joining of dual-phase steel sheets DP600 with the pressing force of 30 kN. The punch and die were deposited by PVD coating of CrN type with LARC technology. The coating state of each 50th manufactured joint was evaluated by SEM. Cracks in the area of punch’s radius were detected. The finite element method was applied for the assessment of punch load in the joining process.

Wear Study of Mechanical Clinching Dies During Joining of Advanced High-Strength Steel Sheets

This study is focused on the wear of the die cavity of the mechanical clinching tool used for joining microalloyed hot-dip galvanized advanced high-strength steel sheets H220PD+Z. Steel sheets were joined using round, single stroke clinching with rigid die with no flexible elements. The joint forming process takes place within the specially formed cavity of the die. Dies and punches for the mechanical clinching were made of tool steel (1.3343 grade) and subsequently covered by three types of PVD coatings: ZrN, CrN, and TiCN ones. The individual die wear was evaluated during the operation period, which means that 300 joints were produced by each die covered with the corresponding coating. The experimental data obtained were compared with the results of FEA numerical simulation, which substantiated the fact that the dominant part of wear is localized in the radius area surrounding the die cavity.

Finite Element Calculation of Clinching with Rigid Die of Three Steel Sheets

The clinching joining of three steel sheets (DC06, DX53D, and H220PD type) was studied by utilization of the finite element method. Clinched joints were also prepared experimentally by joining the above-mentioned steels with the thickness of 0.8 mm (DC06 and DX53D) and 1.0 mm (H220PD). The experimental tool works as single stroke tool, while prepared joints have circular axisymmetric shape, and the rigid die has no flexible segments. Finite element calculations were carried out in ANSYS software under simplified-axisymmetric conditions. Metallographic sections were also prepared from experimentally developed joints to make possible to directly compare the results of simulated and experimental approach. The results of computational approach are discussed and compared to the experimental ones.

Influence of Different Thermochemical Treatments of Bolts on Tightening Parameters of a Bolted Joint

This paper presents the results of the research into the influence of heat treatment, with application of differential parameters and gas atmosphere, on the friction coefficient during the tightening of a bolted joint. The study consisted of several stages – it included metallographic examinations, hardness evaluation and joint tightening tests. This paper presents the research process, the obtained results and the analysis of the impact of thermochemical treatment on functional parameters, such as friction coefficient and torque, during the tightening of a bolted joint.

Mechanical Joining of Various Materials by Clinching Method

Clinching is a simple, cheap and efficient method of joining that enables to join two or more sheets without any additional elements such as rivets, bolts or nuts. In addition, clinching does not require a surface preparation e.g. drilling (riveting), cleaning and roughening of the surface (adhesive boding) and other types of surface preparations (arc welding). Clinching is utilized in a wide range of applications and can be applied to different materials such as low carbon steel sheets, high-strength steel sheets, aluminium alloys, magnesium alloys. The paper presents the results of evaluation of clinched joint properties. The advanced high-strength steel sheet DP600 in combination with the drawing grade steel sheets DC06, DX51D+Z and high-strength low alloy steel sheet H220PD were used for experiments. The influence of position of the sheets relative to the punch and die of the tool on the carrying capacities of the clinched joints was observed as well. The tension test and microhardness test were used for the evaluation of clinched joint properties.

The Structure of the Strength of Riveted Joints Determined in the Lap Joint Tensile Shear Test

Abstract The article presents the analysis of the structure of the load capacity of riveted joints. For the four joining systems the lap joint specimens were made and tested in the shearing test. The joints were prepared for the three combinations of the DC01 steel and EN AW- 5754 aluminium alloy sheets with the thickness of 2mm. On the basis of the obtained load-elongation diagram tensile shear test curves, the basic parameters defined in the ISO/DIS 12996 standard were determined. In the case of the conventional riveted joints the maximum load capacity of the joint is determined by the strength of the fastener. For the joints with aluminium-steel blind rivet , the load capacity of the joint was on the strength limit of the rivet tubular part and on the strength limit of the sheet material. The strength of the SSPR joint is determined by the mechanical properties of the material of the joined sheets. From all sheets and rivet specimens arrangements the highest load capacity of the joint was obtained for the DC01 sheet material joints, and the lowest load capacity of the joint was obtained for the EN AW-5754 sheet material joints.

Automating the modelling process of involute spur gears with straight teeth

In the paper the possibility of using Delphi programming language in the design of the tooth profile was presented. A developed numerical application was used to generate a tooth profile of involute cylindrical gears with modification and without modification. The size of modifications of the tooth root and the addendum was compared with the parameters obtained from the analytical calculations and machining simulation of gears.