Friction Welding Of Steel Research Articles

Characterizations of dissimilar friction welding of ST37 and CK60 steels

The aim of the current work is to study the effect of friction welding parameters such as joint design and rotational speed on the microstructure and mechanical properties of ST37 steel to CK60 steel joints. The tensile strength of the joints was determined using notch tensile tests. The hardness was measured across and perpendicular to the interface. Weld toughness was measured using Charpy impact tests. The results of notch tensile tests indicate that the strength of the weld zone is between those of the two components. The toughness of the weld zone was lower than both base materials. The fracture surface showed cleavage features. The round head samples had better results than for the flat ones.

Simulation of friction welding of alumina and steel with aluminum interlayer

Friction welding is a complicated metallurgical process that is accompanied by frictional heat generation and plastic deformation. Since the thermal cycle of friction welding is very short, simulation becomes very significant. In the present work, a finite element-based numerical model has been developed to understand the thermo-mechanical phenomenon involved in the process of friction welding. The developed model is capable of predicting thermal distribution during friction welding of ceramics with metal using an aluminum interlayer for various time increments. Frictional heating at the interfacial region consumes the aluminum interlayer and establishes a bond between alumina and mild steel. Though there is mechanical mixing, the bond is incomplete in the aluminum-alumina interface. Due to the variation of thermal properties between alumina and mild steel, more amount of thermal stress is induced at the joint interface. Numerical simulation predicts the formation of residual stress in the alumina-mild steel side of the interface. This leads to incomplete interlocking that results in poor joint strength.

A sensitivity study of parameters affecting residual stress predictions in finite element modelling of the inertia friction welding process

This study presents a finite element (FE) model capable of predicting the final residual stress field in an inertia friction welded component of a CrMoV steel considering the elastic and inelastic components of strain resulting from mechanical deformation, temperature changes in the material and volumetric changes associated with phase transformations. The material database was improved to include the properties of the child phases involved in the polymorphic transformation during inertia friction welding (IFW) of CrMoV steels, i.e. austenite and quenched martensite, taking different approaches based on existent experimental data from the parent phase (tempered martensite) and material characterisation of the heat affected zone (HAZ) in weld trials. This is the only FE model available in the literature that takes into consideration the effects induced by the transformation strain component of multiple phases in the total strain generated during IFW. Several simulations were run using this FE model in order to address for the first time the sensitivity of the final residual stress field to the individual effects of the microstructural changes, the interrelationship of multiple phases, and to different processing parameters such as the die geometry, clamping history and cooling rates.

A Finite-Element-Based Process Model for Linear Friction Welding of Steels

A Finite-Element-Based Process Model for Linear Friction Welding of Steels

Influence of silver interlayer in dissimilar 6061-T6 aluminum MMC and AISI 304 stainless steel friction welds

Aluminum MMCs are finding greater utility in automobile and aerospace industries. To boost up the application of aluminum MMCs in real-time applications, it is essential to weld these specimens to other engineering materials. There are several research works reporting the lacuna in arc welding of dissimilar aluminum/steel joints, viz., preferential melting of the aluminum alloy and formation of brittle iron-aluminum intermetallics. However, friction welding process illustrates positive sign for its employment to join dissimilar aluminum/steel. Conversely, intermetallic formation is still of concern. Consequently, to overcome this prevailing problem, interlayers are introduced in this study. At first, dissimilar Aluminum MMCs and AISI 304 stainless steel friction welds are experimented with and without the presence of silver interlayer for conceptual understanding and to clarify and confirm the phenomenal terminologies based on literature. Based on this experience, a few trials of dissimilar Aluminum MMCs and AISI 304 stainless steel friction welds with silver interlayer are experimented on trial and error basis to find optimized friction welding parameter values and these values are used in ANOVA software to plot and analyze the parameters inter dependencies. Then, upper and lower limits of friction welding parameters are fixed to achieve good-quality welds. These limits are fed into ANOVA to obtain full factorial trials based on design of experiment (DoE). The weldments are also evaluated using destructive and non-destructive tests. The metallurgical characterizations of weldments are analyzed. Further, a preliminary attempt is made to develop a finite element model to investigate temperature governing phenomenon such as deformation, stress and strain.

Finite element modelling of the inertia friction welding of a CrMoV alloy steel including the effects of solid-state phase transformations

Finite element (FE) process modelling of the inertia friction welding (IFW) between two tubular CrMoV components has been carried out using the DEFORM-2D (v10.2) software. This model has been validated against experimental test welds of the material; this included process data such as upset and rotational velocity as well as thermal data collected during the process using embedded thermocouples. The as-welded residual stress from the FE model has been compared to experimental measurements taken on the welded component using the hole drilling technique. The effects of the solid-state phase transformations which occur in the steel are considered and the trends in the residual stress measurements were well replicated when compared to the experimental data.

Developing a Mathematical Model to Predict the Optimum Friction Phase Parameters for Friction Welding of High Speed Steel to Medium Carbon Steel

This work was carried out in order to optimize the friction phase parameters, of friction welding of M2 high speed steel, to AISI 1040 medium carbon steel, namely; rotational speed, friction pressure and friction time. The experiments were designed as per Taguchi method. The optimization of the experimentally obtained results was carried out by trying three mathematical models, namely; a multiple linear regression model without interaction effect, a multiple linear regression model with interactions effect, and a second-order polynomial regression model. The three models were evaluated using the experimental data, the coefficient of multiple determination R², and Standard error of the regression (S), were used as the evaluation criteria of the models. The polynomial model was chosen, and optimized using a Genetic Algorithm. The optimal value of the joint strength of 411 MPa was obtained at the highest value of the time ( 44.9 sec.) and the pressure of 112 MPa and the speed of 1349 r.p.m.

3D Finite Element Analysis of the Effect of Process Parameters on Linear Friction Welding of Mild Steel

In this work, a 3D numerical model was developed to investigate the complicated thermo-mechanically coupled process of linear friction welding (LFW). The explicit-implicit alternate method was adopted for the first time to simulate LFW mild steel based on the ABAQUS software. To cope with the excessive element distortion, remeshing was conducted at certain calculation time with the help of the HYPERWORKS software. Results show that the interface temperature is quickly increased to near 900 °C within 1 s. With increasing the welding time, the interface temperature reaches a quasi-steady state of about 950 °C and the axial shortening rate keeps almost constant. A final unilateral axial shortening of 2.73 mm was obtained under the experiment condition, which corresponds well to the experiment. Moreover, the effects of processing parameters (oscillation frequency, oscillation amplitude, and friction pressure) on the joint temperature evolution and axial shortening were systematically examined and discussed. These three parameters could be integrated into one factor, i.e., heat input to the interface.

The Microhardness Analysis of Friction Welded AISI 52100 Grade Carbon Steel Joints

The solid-state joining process produces welds with improved mechanical properties and reduced distortion. Higher Carbon Steels are extensively used in different industrial applications such as shipbuilding and automobile industries due to their superior mechanical properties. In this work, friction welding of high carbon steel of Φ12mm dia extruded rod was studied with a plan to analysis the hardness behavior on the weldment. Welds are made with a high and low level range of process parameter combinations (incorporating ANOVA methods) which were subjected to Vickers Hardness tests. The Vickers Hardness of the welded joints has been reported.

Friction welding of a nickel free high nitrogen steel: influence of forge force on microstructure, mechanical properties and pitting corrosion resistance

In the present work, nickel free high nitrogen austenitic stainless steel specimens were joined by continuous drive friction welding process by varying the amount of forge (upsetting) force and keeping other friction welding parameters such as friction force, burn-off, upset time and speed of rotation as constant at appropriate levels. The joint characterization studies include microstructural examination and evaluation of mechanical (micro-hardness, impact toughness and tensile) and pitting corrosion behaviour. The integrity of the joint, as determined by the optical microscopy was very high and no crack and area of incomplete bonding were observed. Welds exhibited poor Charpy impact toughness than the parent material. Toughness for friction weld specimens decreased with increase in forge force. The tensile properties of all the welds were almost the same (irrespective of the value of the applied forge force) and inferior to those of the parent material. The joints failed in the weld region for all the weld specimens. Weldments exhibited lower pitting corrosion resistance than the parent material and the corrosion resistance of the weld specimens was found to decrease with increase in forge force.

Finite Element Modeling of the Inertia Friction Welding of Dissimilar High-Strength Steels

Finite element (FE) process modeling of inertia friction welding between dissimilar high-strength steels, AerMet® 100 and SCMV, has been carried out using the DEFORM™-2D (v10.0) software. This model was validated against experimental data collected for a test weld performed between the materials; this included process data such as upset and rotational velocities as well as thermal data collected during the process using embedded thermocouples. The as-welded hoop residual stress from the FE model was also compared with experimental measurements taken on the welded component using synchrotron X-ray and neutron diffraction techniques. The modeling work considered the solid-state phase transformations which occur in the steels, and the trends in the residual stress data were well replicated by the model.

Heat reflux in flash and its effect on joint temperature history during linear friction welding of steel

A 2D numerical model was developed to investigate the effect of flash on the joint temperature field during the cooling phase of linear friction welding (LFW). The LFW experiments and analytical heat loss analysis calculations validated this observation. Experiments show that the heat loss rate of the flash root is lower than that of the weld center during the cooling phase of LFW, which is observed in the model as well. Furthermore, analysis of the heat losses during the cooling phase of LFW shows that 90.7% of the flash heat is dissipated through conduction, pointing to the importance of flash heat reflux on the joint temperature.

Dissimilar friction welding of induction surface-hardened steels and thermochemically treated steels

Results on friction welding of surface-hardened steels are analyzed based on experiments using induction-hardened steels as pivotal component, joined with quench-hardened steels and steels thermochemically treated by carburization and nitriding, respectively. Higher axial pressure needs to be applied, in order to fully expunge the hardened layers from the joining plane. A smooth surface for the burr, without cracks, can be obtained for adequate welding parameters and the burr can be subsequently removed without major risks, immediately after the friction welding process ends. For joining an induction hardened C55 steel with a quenched hardened C55 steel, the maximal friction pressure has to be limited to about 200N/mm2, in order to avoid materials separations in the centre of the joint. High axial pressures lead to good mechanical characteristic for friction welding an induction-hardened 34CrNiMo6 steel with a carburized 16MnCr5 steel. Friction welding of an induction-hardened C55 steel with a C45 nitrided steel showed that an increase of the friction upset distance to 6mm favours the complete expulsion of the nitride debris, with positive effects on the quality and mechanical properties of the joint.

Friction welding of steel to ceramic

The goal of this paper is to give a clear summary of the literature review performed during the master thesison friction welding on dissimilar materials. Of main interest for this work is the welding of steel to a ceramicmaterial such as alumina (Al2O3Almost all research articles that have been found in open literature state that welding steel to a ceramic isnearly impossible without using an interlayer consisting of a compatible metal. The most frequently reportedtype of weld is steel to alumina with an aluminium interlayer. For this reason the literature study included inthis thesis, also focuses on friction welding of aluminium to steel and aluminium to ceramic. A detailedexplanation will be given for the most challenging difficulties like the creation of a brittle intermetalliccompound layer in a steel-aluminium weld interface and the creation of fatal thermally induced stresses inan aluminium-ceramic weld interface. Both of these problems must be dealt with in order to produce astrong bond. A redesigned rotary friction welding machine is currently being assembled and will be used forthe experimental part of this research.). Because of the difficulties involved in producing a sound weld for thismaterial combination, not a lot of literature is available on this topic. This paper starts with a discussion onthe basics of friction welding and typical problems encountered in welding of steel to ceramic.

Role of nickel as an interlayer in dissimilar metal friction welding of maraging steel to low alloy steel

Continuous drive friction welding of dissimilar metals, maraging steel and low alloy steel was carried out. It was observed that the hardness, ductility and impact toughness of maraging steel are low due to the diffusion of elements such as carbon, manganese, silicon and phosphorus from low alloy steel to maraging steel. An attempt was made in this study to improve the properties by friction welding of maraging steel and low alloy steel with nickel as an interlayer. The hardness, tensile strength and impact toughness are observed to be improved, as nickel acted as diffusion barrier. The effect of post-weld heat treatments on microstructure and mechanical properties of dissimilar metal friction welds with and without interlayer was also studied. Maraging steel responded to solutionizing & aging and low alloy steel responded to quenching and tempering. The notch tensile strength and impact toughness in case of dissimilar metal weld with interlayer are observed to be more than that of the dissimilar metal weld without interlayer.

A statistical analysis of rotary friction welding of steel with varying carbon in workpieces

Nowadays, friction-welding method is accepted in many industries, particularly for joining dissimilar materials as a mass production process. It is due to advantages like less material waste, low production time, and low energy expenditure in it. The effect of change in carbon contents in steel is studied experimentally in friction-welding process and a statistical model is developed. An experimental setup was designed and produced to achieve the process with equal diameter workpieces. Continuous/direct drive friction-welding process is chosen in which transition from friction to forging stage can be achieved automatically by applying a brake. In this experimentation, workpieces with different carbon in each were welded with workpieces having same carbon contents. Response surface methodology of design of experiment is used to analyze the results. Friction welding is carried out with change of speed, forging pressure, and carbon content while keeping other parameters as constant. Tensile strength and hardness variations were obtained and examined in the post-weld at the joint of workpieces. The optimum welding parameters for the joints were obtained. Mathematical equations in terms of each output parameter are then validated experimentally.

Modeling of continuous drive friction welding of mild steel

In this study, a two-dimensional model was developed for continuous drive friction welding (CDFW) of mild steel based on the redevelopment environment of ABAQUS software. The influences of axial pressure and rotating speed on interface temperature and axial shortening were examined. The results show that increasing axial pressure, the weld interface can reach a quasi-stable temperature more quickly and the axial shortening will be larger. Similar findings were observed with increasing the rotating speed. In addition, with the increase of friction time, the interface temperature remains stable and axial shortening increases linearly with time. Experiments with mild steel bars were also conducted. The simulation results are comparable to the experiments.

Friction Welding of Spheroidal Graphite Cast Iron and Mild Steel

Friction Welding of Spheroidal Graphite Cast Iron and Mild Steel

Energy and force analysis of linear friction welds in medium carbon steel

The linear friction welding process is rapidly developing into an important manufacturing technology for high quality joining of engineering materials. The energy required for linear friction welding is an important issue due to economic and environmental reasons, but is not currently fully understood. This paper describes a comprehensive evaluation of the energy input during linear friction welding of a medium carbon steel with different process parameters. This calculation is based on an analysis of force and displacement data from the machine, which takes momentum into account. The analysis shows that energy input to the weld is minimised with high frequencies and rubbing velocities; however, there is a considerable amount of energy lost in oscillating the machine tooling under these conditions. Furthermore, analysis of the force indicates that a peak load occurs just before the samples being aligned, which is probably caused by ploughing of the samples during welding.

Mechanical evaluation and thermal modelling of friction welding of mild steel and aluminium

In friction welding of two dissimilar materials, two rods are welded together by holding one of them still while rotating the other under the influence of an axial load which creates frictional heat in the interface. In this study, mechanical properties of mild steel and aluminium welded rods were evaluated to understand the thermal effects, and an explicit one-dimensional finite difference method was used to approximate the heating and cooling temperature distribution of the joint. The thermal effects of the friction welding were observed to have lowered the welded materials hardness compared to the parent materials. The tensile strength of the welded rods is lower than the parent rods due to incomplete welding. The preliminary predictions were compared to actual thermocouple data from welds conducted under identical conditions and were shown to be in fair agreement. The finite difference method proposed in this work will provide guidance in weld parameter development and will allow better understanding of the friction welding process.