Joint Quality Research Articles

The Feasibility of Static Shoulder Friction Stir Welding in Joining Dissimilar Metals of Al6061 and Ti6Al4V

In this study, static shoulder friction stir welding (SSFSW) is innovatively employed to join Al6061 and Ti6Al4V, aiming to minimize material mixing and intermetallic formation, significantly influencing the interfacial microstructure and joint strength. The results revealed that SSFSW reduced the intermetallic layer thickness at the interface, improving joint quality. The mutual interdiffusion of Al and Ti at the interface was influenced by an exothermic chemical reaction, forming an Al5Ti2–Al3Ti sequence due to the diffusion of Al into the Ti matrix. The microstructural analysis demonstrated better interfacial microstructural homogeneity in SSFSW joints than conventional FSW (CFSW), with finer titanium particle distribution. The larger particles resulted in coarser grains in CFSW, affecting the mobility of dislocations, which potentially led to the inhomogeneous concentration of dislocations at the interface. Recrystallization mechanisms varied between CFSW and SSFSW, with the Ti interface showing equiaxed and recrystallized grains due to the dynamic recovery driven by adiabatic shear bands. The tensile testing results of SSFSW exhibited a joint efficiency of 88%, demonstrating a 20.2% increase compared to CFSW, which can be attributed to differences in fracture modes. This study contributes to an understanding of dissimilar Al-Ti joining and provides insights for industries seeking to leverage the benefits of such combinations in lightweight and high-performance structures.

Effectiveness of Muscle Strengthening Exercises on Joint Pain among the Late Middle Age Group in Bordowali Health and Wellness Centre, Agartala, West Tripura

The researcher conducted a study on effectiveness of Muscle strengthening exercises on joint pain among the late middle age group in Bordowali Health and Wellness Centre, Agartala, West Tripura. Objectives: The objectives of the study were to assess the pre-existing level of joint pain among the late middle age group, to evaluate the effectiveness of Muscle strengthening exercises on joint pain among the late middle age group, and to find out the association between pre-existing level of joint pain among the late middle age group with their selected demographic variables. Method: The present study’s conceptual framework was based on Modified Wiedenbach’s Helping Art of Clinical Nursing Theory (1964). A quantitative evaluative research approach, pre-experimental one group pre-test post-test research design and purposive sampling technique were used for the study. Data collection: Data were collected from 40 late middle age group through interview technique by administering the socio-demographic proforma and Modified pain scale on joint pain, stiffness and quality of life. Active Muscle strengthening exercises were provided as an intervention for 35 minutes daily for 20 consecutive days. On 20th day, post-test was taken through interview technique by administering the Modified pain scale on joint pain, stiffness and quality of life. Result: The result showed that the mean post-test level of pain score of joint pain among the late middle age group (34.27±12.94) was lower than the mean pre-test level of pain score (63.15±16.92) with mean difference of 28.88. Paired ‘t’ test value (8.59) was also found significant at 0.05 level of significance (df=39, table value=2.02). Analysis of Variance (ANOVA) ‘F’ value showed there was a significant association between pre-test level of joint pain among the late middle age group with their selected demographic variables - type of family [‘F’ value=3.86, table value=3.23, df between group – 2, within group – 37], total number of family members staying with you [‘F’ value=3.31, table value=3.23, df between group – 2, within group – 37], duration of suffering from joint pain [‘F’ value=5.52, table value=3.23, df between group – 2, within group – 37] which were significant at 0.05 level of significance. Conclusion: The findings of the present study concluded that Muscle strengthening exercises were an effective measure to reduce the level of joint pain among the late middle age group.

Analysis of Electric Current on Aluminum Plate Welding Using MMA (Manual Metal Arc) Method

Many industries depend on welding, which joins materials with heat. This research focuses on Manual Metal Arc (MMA) welding aluminum plates due to its adaptability for thin materials and compatibility with aluminum's unique properties. The study investigates how electric current affects aluminum plate MMA welding, improving welding methods. The study examined the effect of electric current on aluminum plates using the MMA method using a qualitative descriptive research design. Sorong Merchant Marine Polytechnic's workshop laboratory conducted the research from February to May 2023 using AWS E 6013 welding electrodes and ASTM A36 plates. Data was collected through observation, documentation, and literature review, then analyzed using data reduction principles. Results show that electric current variation significantly affects welding characteristics. Increased amperage penetrates deeper, but excessive current can melt and weaken joints. Amperage, weld rate, joint quality, and penetration depth must be balanced. The study emphasizes precise welding control, improving welding efficacy. The complex relationship between critical parameters emphasizes the need for careful equilibrium and the importance of following welding guidelines and parameters in the Welding Procedure Specification. As inadequate or excessive current can affect weld quality, this research improves MMA aluminum plate welding results.

Numerical and experimental study of underwater friction stir welding of 1Cr11Ni2W2MoV heat-resistant stainless steel

Due to the benefits of solid-state joining, friction stir welding (FSW) has seen an increase in applications in the aircraft and automotive industries. However, short tool life and heat-affected zone (HAZ) softening are the two main issues with the FSW of advanced high-strength steel. In this study, the underwater friction stir welding (UFSW) of 1Cr11Ni2W2MoV steel was investigated and compared to the Normal friction stir welding (NFSW). Besides, a 3-D thermo-mechanical finite element model was developed to understand the effect of the different cooling mediums and tool rotation rates on the thermal cycles, plastic deformation, tool wear, and microstructure evolution. The simulation results revealed that the stir zone (SZ) of the UFSW exhibits lower peak temperatures and smaller plastic strain compared to the NFSW. The experimental results showed that a high tool rotation rate can be used during UFSW without causing overheating of the workpiece and tool materials resulting in high joint quality and low tool wear. The M23C6 and Fe3C carbide fractions in the HAZ at UFSW are lower than that at NFSW. The UFSW reduces the soft HAZ's width and increases its hardness. The ultimate tensile strength was increased by 17 %, and the HAZ width was decreased by 35 % at UFSW compared to that at NFSW.

Ultrasonic spot welding of open-cell Cu foam and Al plate: A study on the quality of joints

As a type of novel material, open-cell copper (Cu) foam has been widely applied in electrode production of batteries, due to its functional and structural properties. The use of ultrasonic welding technique to join Cu foam and aluminium (Al) plate has been proven to be feasible, but quality evaluation of the joints remains a blank to be filled in. In this study, orthogonal test design is used to investigate the effects of welding pressure, welding amplitude, welding energy and the interaction among the three parameters on the shear-tensile strength of ultrasonically welded joints of Cu foam/Al plate, and it is influenced by the three parameters in the following order: welding pressure > welding energy > welding amplitude. Based on the results of the orthogonal test, a Cu foam/Al plate ultrasonic welding joint evaluation system is established, based on which, qualitative and quantitative analysis on the quality of the joints classified the joints into three grades. The optimal parameter combination of the welding joint of Cu foam/Al plate is obtained as follows: 0.5 MPa, 65 %, 130 J, under which the porous structure of the joint is complete while its tensile strength is equal to or even better than the base material.

Mechanically Joined Extrusion Profiles for Battery Trays

In the context of electromobility, ensuring the leak tightness of assemblies is of paramount importance, particularly in battery housings. Current battery housings, often featuring base assemblies crafted from extruded aluminum profiles, address the challenge of leak tightness at joints through methods like friction stir welding, a process known for its time and cost intensiveness. The aim of this study is to develop and implement a new type of extruded profile concept to produce tight base assemblies for battery housings by a longitudinal mechanical single stroke joining process. The geometry, the process and the properties of the aluminum profiles are investigated to get a joint that meets the tightness requirements and achieve high load-bearing capacities in agreement with the high homologation requirements set to vehicles with high-voltage systems. The joint is formed by means of a single stage press stroke, which eliminates the need for complex tool designs that are necessary for continuous joining (roll joining). Flat steel contact surfaces are used as joining tools. To evaluate the joint quality, force curves from the joining process are analyzed and the resulting joint geometries are assessed using micrographs. The resulting leak tightness of the linear joints is measured by a helium sniffer leak detector and the load-bearing capacities are investigated by shear lap and bending tests and fatigue strength test. The study also explores whether a difference in strength between the two joining partners has a positive effect on the joint properties.

Theoretical and Experimental Studies of the Shock-Compressed Gas Parameters in the Welding Gap.

This work is devoted to the study of the processes that take place in the welding gap during explosive welding (EW). In the welding gap, when plates collide, a shock-compressed gas (SCG) region is formed, which moves at supersonic speed and has a high temperature that can affect the quality of the weld joint. Therefore, this work focuses on a detailed study of the parameters of the SCG. A complex method of determining the SCG parameters included: determination of the detonation velocity using electrical contact probes, ceramic probes, and an oscilloscope; calculation of the SCG parameters; high-speed photography of the SCG region; measurement of the SCG temperature using optical pyrometry. As a result, it was found that the head front of the SCG region moved ahead of the collision point at a velocity of 3000 ± 100 m/s, while the collision point moved with a velocity of 2500 m/s. The calculation of the SCG temperature showed that the gas was heated up to 2832 K by the shock compression, while the measured temperature was in the range of 4100-4400 K. This is presumably due to the fact that small metal particles that broke off from the welded surfaces transferred their heat to the SCG region. Thus, the results of this study can be used to optimize the EW parameters and improve the weld joint quality.

An enhanced technique for friction stir welding of ceramic particle reinforced aluminium based metal matrix composites

AbstractThis manuscript proposes an enhanced technique for the friction stir welding (FSW) of ceramic particle‐reinforced aluminium‐related metal matrix composites. The proposed technique is the joint implementation of both the Aquila Optimizer and Pelican Optimization Algorithm. This proposed method aims is to enhance the welding efficiency, quality, and overall performance of the weld joints. The test is conducted in an all‐purpose machine at cutting speeds that permit temperatures that are comparable to the FSW of stainless‐steel, aluminium alloys and copper. Reaction–diffusion studies are conducted to better understand the diffusion‐control process under tool wear, and the tool wear rate is determined by the length of the cutting tool's nose tip. Rotational speed at 10 mm/min is examined. SiC exhibits the highest performance of aluminium and stainless steel. As the fraction of SiC increases to 18%, the axial force and rotational speed of FSW also increase.

3D BIOPRINTING TISSUE-ENGINEERED MENISCAL CONSTRUCTS

Meniscal injuries affect over 1.5 million people across Europe and the USA annually. Injury greatly reduces knee joint mobility and quality of life and frequently leads to the development of osteoarthritis. Tissue engineered strategies have emerged in response to a lack of viable treatments for meniscal pathologies. However, to date, constructs mimicking the structural and functional organisation of native tissue, whilst promoting deposition of new extracellular matrix, remains a bottleneck in meniscal repair. 3D bioprinting allows for deposition and patterning of biological materials with high spatial resolution. This project aims to develop a biomimetic 3D bioprinted meniscal substitute.Meniscal tissue was characterised to effectively inform the design of biomaterials for bioprinting constructs with appropriate structural and functional properties. Histology, gene expression and mass spectrometry were performed on native tissue to investigate tissue architecture, matrix components, cell populations and protein expression regionally across the meniscus. 3D laser scanning and magnetic resonance imaging were employed to acquire the external geometrical information prior to fabrication of a 3D printed meniscus. Bioink suitability was investigated through regional meniscal cell encapsulation in blended hydrogels, with the incorporation of growth factors and assessed for their suitability through rheology, scanning electron microscopy, histology and gene expression analysis.Meniscal tissue characterisation revealed regional variations in matrix compositions, cellular populations and protein expression. The process of imaging through to 3D printing highlighted the capability of producing a construct that accurately replicated meniscal geometries. Regional meniscal cell encapsulation into hydrogels revealed a recovery in cell phenotype, with the incorporation of growth factors into the bioink's stimulating cellular re-differentiation and improved zonal functionality.Meniscus biofabrication highlights the potential to print patient specific, customisable meniscal implants. Achieving zonally distinct variations in cell and matrix deposition highlights the ability to fabricate a highly complex tissue engineered construct.Acknowledgements: This work was undertaken as part of the UK Research and Innovation (UKRI)-funded CDT in Advanced Biomedical Materials.

Thermal modeling of friction stir welding of thick high-density polyethylene plates

The process temperatures in the friction stir welding of thick polymer plates play a significant role in the joint's quality since the process is characterized by mixed solid and viscous flow states. The heat generation mechanism in each state is fundamentally different, with heat being generated by friction in the solid-state and by viscous shear flow in the viscous state. In this study, the heat generation and dissipation in the friction stir welding of 14 mm thick high-density polyethylene plates were studied numerically through solving the direct heat conduction problem. Two models of heat generation were used in the numerical solution and the effect of the pin rotational speed on the process temperatures was investigated. It was shown that the utilization of a mixed heat generation model consisting of both the solid state and the viscous shear flow considerably improves the numerical model predictions. The temperature predictions were validated through welding experiments and showed a temperature difference of 3 %. Furthermore, it was found that the welding process stabilizes at rotational speeds higher than 800 rpm, where no considerable change occurs in the volume of the viscous flow region and the welding power requirement. The numerical results based on the combined solid-viscous heat model were in good agreement with the experimental thermal histories.

Evaluating Welding Electrode Angle and Root Gap Effects on Joint Quality

Welding is a type of manufacturing method that offers greater advantages than riveting for combining metals or sheets. By adjusting the welding process parameters to predict welding strength, a higher quality of joint can be achieved. In this study, the weld processing parameters welding current (WC), electrode angle (EA), and root gap (RG) were taken into account. We performed destructive testing, such as tensile and hardness tests, to evaluate the metal piece's weld strength after it had been joined. Stainless steels and carbon steels, two unrelated materials, were used in this project. The Taguchi method was used to carry out joint processes in arc welding (AW), and nine samples were produced by altering the input parameters. Steel alloy 308L has been used as the electrode for forming connections.

Identification of weld sub-surface defects by radiographic images using texture features

Non-Destructive Testing (NDT) is important to detect sub-surface defects in the weldments to ensure the quality of weld joints. The weld radiographs are digitized using a high-resolution digital camera. Data augmentation techniques are applied to expand the radiographic image dataset. Multi-class defect classification is done using the Gray-level co-occurrence matrix as a feature extractor and these features are given as input to various classifiers for classifying slag inclusion, incomplete penetration, and acceptable weld bead classes. The proposed methodology achieved the highest accuracies of 84%,83%,80%,70%, and 64% respectively for GLCM plus Random Forest, GLCM plus XGBoost, GLCM plus lightGBM, GLCM plus KNN, and GLCM plus SVM. The technology of applying ML techniques on radiographic images in detection of defects in welding as well as other manufacturing processes can be a sustainable practice.

Mechanical Properties of FSW Joints Magnesium Alloy at Different Rotational Speeds

Magnesium (Mg) has become a focus in the transportation industry due to its potential in reducing fuel consumption and gas emissions while improving recyclability. Mg alloys are also known for their low neutron absorption, good resistant of carbon dioxide as well as thermal conductivity which makes them suitable for use in industrial equipment for nuclear energy. there has been an increasing interest in the research and development of Mg alloys. These are the lightest of all metallic structural materials and are approximately 33% lighter than aluminium (Al) and 75% lighter than ferrous (Fe) alloys and have excellent specific mechanical properties. In this work, FSW of AZ31B Alloy was examined at the various rotational speeds of 900 -1440 rpm, with fixed welding speed of 40mm/min and 2° tool tilt angle using an HSS tool. The mechanical properties were compared for the different rotational speeds. The quality of FSW joints is dependent on input value of heat and material flow rate, which are prejudiced by process parameters., higher rotation speeds may cause abnormal stirring, resulting in a tunnel defect at the weld nugget due to increased strain rate and turbulence.

Review on Hybrid Welding Techniques for Improved Joint Performance

The process of welding is extensively employed in diverse industrial sectors for the purpose of material joining. The integrity of components or structures is significantly dependent on the quality and performance of welded joints. Nevertheless, conventional welding techniques present certain restrictions, including reduced welding velocity, substandard joint characteristics, and deformation. Hybrid welding techniques have surfaced as a viable solution in recent times to address the limitations and enhance the joint performance.The present study provides a thorough examination of diverse hybrid welding methodologies, encompassing laser-arc hybrid welding, friction stir welding, and hybrid laser welding. The manuscript examines the operational mechanisms, benefits, and constraints of every method. Moreover, the paper presents findings from recent research studies that have examined the collective efficacy of these methodologies across various materials and contexts.The findings indicate that the utilisation of hybrid welding methods has the potential to enhance joint performance through the improvement of mechanical properties, reduction of defects, and minimization of distortion. The manuscript additionally examines the obstacles and prospective avenues in the realm of hybrid welding. The research presented herein offers significant insights for both researchers and practitioners operating within the welding industry. Specifically, it provides guidance on the selection of optimal welding techniques for applications, as well as the optimisation of welding parameters to enhance joint performance.

Zavarivanje okretnih postolja primjenom visokoučinskog postupka zavarivanja

Bogies are integral elements of wagons that enable easier passage of railway vehicles through a curve by reducing friction and wear between the wheels and the rail. The axle assemblies and traction motor of the vehicle are attached to the bogie. In accordance with the standard EN 15085-2 classification level CL1, requirements have been set for the quality of welded joints of railway vehicles and certain components, with regard to the requirements, today bogies are produced in the company ĐĐSV using conventional welding procedures. The paper presents the application of current technology in the welding of turntables, as well as the test results and application of the robotic TWIN welding process.

Underwater Friction Welding of Low Carbon Steel

In this study, an attempt was made to obtain a welded joint from the underwater friction welding (UFW) process. The workpiece material used in this experiment was AISI 1018 low carbon steel. The experiment was carried out on a friction welding machine which was designed and manufactured for this purpose. The UFW process was carried out by varying the spindle rotation used to rotate one of the workpieces. The friction force was kept constant. The quality of the welded joints resulting from UFW was determined by measuring the misalignment that occurs in the weld joint, the macro and micro structures formed, as well as the mechanical properties of the welded joint. For comparison, friction welding in air (FW) was also carried out. The results obtained indicate that low spindle rotation results in high misalignment of the welded joint between the two workpieces. During the UFW process, rapid cooling occurs so that the microstructure of the weld metal, TMAZ and HAZ is dominated by a fine pearlite phase so that the hardness and strength of the weld joint are higher than those produced by FW process in air.

Effects of Resistance and Proprioceptive Training on an Athletic Population with Chronic Ankle Instability: A Scoping Review

<b>Background:</b> One in three athletes who suffer a sprain will end up with chronic ankle instability (CAI) due to re-injury or inadequate recovery, with symptoms that can last for more than 12 months. Resistance and proprioceptive training have been shown to have a positive effect on the rehabilitation of CAI, improving perceived instability, balance, functional ability, strength, and quality of life. However, the right type of training, dosage, and intensity are currently unclear on many points. <b>Aim:</b> The aim of this review is to investigate current literature addressing the effects of resistance and proprioceptive training on improving the symptoms of athletes with CAI. The individual efficacy of each training type (resistance and proprioceptive) was investigated and compared to each other. Furthermore, it was examined whether the combined application of both training methods within a single treatment regimen provides greater benefits than their separate use. <b>Method:</b> The MEDLINE, ScienceDirect, PEDro, CINAHL, SPORTDiscus, and EMBASE databases were searched using different combinations of the following key words: chronic ankle instability, athletes, proprioceptive exercise, resistance exercise, and rehabilitation. The review included clinical studies that were applied to professional or amateur athletes with CAI from 1998 to the present. These studies included protocols for resistance and/or proprioceptive exercise programs that were applied independently or in combination with other therapy regimens. <b>Results:</b> Eighteen clinical trials were included in this review: three on resistance training, five on proprioceptive training, and ten on both. The Physiotherapy Evidence Database (PEDro) was used to assess the quality of all articles. <b>Discussion:</b> Both types of training, resistance and proprioceptive, improve perceived instability, static and dynamic balance, functional ability, strength and, quality of life in the athletic population with CAI. However, better results appear to be derived from combined protocols that include both types of exercises. <b>Conclusions:</b> Four to six weeks of a combined resistance and proprioceptive exercise program may increase the strength of the ankle joint muscles, dynamic balance, functional ability and quality of life in athletes with CAI.

The impact of metabolic syndrome on clinical outcomes following total knee arthroplasty in osteoarthritis patients.

Metabolic syndrome (MetS) is a combination of interconnected conditions, including insulin resistance, abdominal obesity, high blood pressure, and abnormal blood lipid levels. The objective of this research was to investigate the impact of MetS on the quality of life and clinical outcomes following total knee arthroplasty (TKA) in patients with osteoarthritis (OA). A retrospective descriptive study was conducted to enroll OA patients who underwent primary TKA at Zhongda Hospital, Southeast University from January 2015 to August 2019. A total of 83 OA patients who did and 144 (MetS group) who did not have MetS (non-MetS group) were included. An analysis was conducted on the patient's clinical data. The two groups had similar results in terms of lengths of stay (P=0.93), hospital costs (P=0.24), and overall complication rates (P=0.99). There was no significant difference in the average erythrocyte sedimentation rate and C-reactive protein levels between the groups. However, the MetS group exhibited notably lower Hospital for Special Surgery knee scores and Short Form [36] health survey (SF-36) scores compared to the non-MetS group (both P>0.05) during the one-year follow-up period. OA patients who have MetS had significantly worse knee joint function and quality of life after TKA. There are certain constraints in the current research. First, it belongs to a single-center retrospective study. Further study will be necessary to determine the generality of this conclusion. Second, this study is retrospective, and the number of patients included is not large. Third, due to the diverse clinical groups in our hospital, it is challenging to comprehensively document all the clinical data of the patients involved in this study. Forth, this study did not compare the preoperative differences between the two groups, as well as analyze the postoperative improvement changes in depth. We will compare the preoperative and postoperative differences between the two groups in more depth in future large sample studies.

Comparison of mini-plate versus Kirschner wire internal fixation for fifth metacarpal basal fractures with carpometacarpal joint dislocation.

To compare the outcome of mini-plate versus Kirschner wire (K-wire) internal fixation for treating fifth metacarpal basal fractures with carpometacarpal joint dislocation. A total of 46 patients with fifth metacarpal basal fractures combined with carpometacarpal joint dislocation were divided into two groups. The control group received K-wire fixation, while the observation group underwent mini-plate fixation. We assessed treatment effectiveness, surgical parameters, range of motion, serum stress markers, quality of life scores, and postoperative complication rates. A multivariable logistic regression analysis was performed to identify factors influencing postoperative joint function. The observation group demonstrated a significantly higher excellent and good rate compared to the control group (P<0.05). Additionally, the observation group had a lower intraoperative bleeding volume, shorter incision lengths, and faster fracture healing times, all significant differences (all P<0.05). Postoperative assessments indicated that range of motion, quality of life scores, and superoxide dismutase levels were significantly improved in the observation group (P<0.05). Conversely, cortisol, angiotensin II, and norepinephrine levels, along with the incidence of postoperative complications, were lower in the observation group compared to the control group (all P<0.05). Logistic regression analysis identified the surgical method as an independent factor affecting postoperative metacarpal joint function (OR = 0.16, P = 0.003). Mini-plate internal fixation is superior to K-wire fixation for the treatment of fifth metacarpal basal fractures with carpometacarpal joint dislocation. It promotes faster fracture healing, reduces serum stress markers, enhances joint mobility and quality of life, and decreases postoperative complications.

Effectiveness of Bach Nien Kien Health Supplement in the Treatment of Patients With Symptomatic Knee Osteoarthritis.

Knee osteoarthritis (KOA) is the most common disease in adults. We conducted a clinical study to evaluate the efficacy and safety of Bach Nien Kien (BNK) in supportive therapy for patients with symptomatic KOA. An open interventional study was performed on 60 patients aged 38 to 70 with the diagnosis of symptomatic KOA. The patients were assigned to a study group (SG) with 30 subjects and a control group (CG) with 30 subjects using a matching method. The patients in SG were treated with electroacupuncture, glucosamine supplement, and BNK, while the patients in CG received the same treatment without BNK. At the end of the 30-day treatment (d30), the SG had a reduction in VAS score compared to a pre-treatment level of 3.03±0.96 points, which was more than the CG of 2.5±0.90 points. The excellent result in the SG was 10%, and the CG had no excellent result. The good result in the SG was 56.7%, and the CG group was only 26.7%. The moderate and poor results in the CG were high, 63.3%, and 10%, respectively; in the SG, only 26.7% and 6.7%. The difference in overall treatment results between the SG and CG was statistically significant (p<0.05). During the 30-day treatment period in both groups, no patient reported any undesirable effects. Bach Nien Kien health supplement is effective and safe for controlling KOA symptoms and improving joint motion and quality of life for patients with symptomatic KOA.