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The present investigations aims to improve weld characteristics of Aluminum (Al-6001) plate using a pulsed TIG welding. The welding speed of the current study has been controlled by PUG machine coupled with TIG machine for automatic operation. The similar welding of the of Al-6001 plate have been performed by varying welding process parameters for full depth of penetration. Single side welding of Al-6001 plate has been studied. The influence of welding current & welding speed on the weld characteristics of the welded joint have been studied. The weld zone features have been analyzed with the microstructure images using Optical Microscopic and SEM (Scanning electron microscope) and on the other hand different phases have been characterized using XRD (X-ray diffraction) analysis. The hardness variation across the weld zone has also been quantified to study the change in mechanical property of the welded zone.

The prevalence of different cancers after heart transplant (HT) is unclear due to small and conflicting prior studies. Herein, we report a systematic review and meta-analysis to highlight the prevalence and pattern of malignancies post-HT. We conducted an extensive literature search on PubMed, Scopus, Cochrane databases for prospective or retrospective studies reporting malignancies after HT. The proportions from each study were subjected to random effects model that yielded the pooled estimate with 95% confidence intervals (CI). Fifty-five studies comprising 60,684 HT recipients reported 7759 total cancers during a mean follow-up of 9.8 ± 5.9 years, with an overall incidence of 15.3% (95% CI = 12.7%-18.1%). Mean time from HT to cancer diagnosis was 5.1 ± 4 years. The most frequent cancers were gastrointestinal (7.6%), skin (5.7%), and hematologic/blood (2.5%). Meta-regression showed no association between incidence of cancer and mean age at HT (coeff: -0.008; P = 0.25), percentage of male recipients (coeff: -0.001; P = 0.81), donor age (coeff: -0.011; P = 0.44), 5-year (coeff: 0.003; P = 0.12) and 10-year (coeff: 0.02; P = 0.68) post-transplant survival. There is a substantial risk of malignancies in HT recipients, most marked for gastrointestinal, skin, and hematologic. Despite their occurrence, survival is not significantly impacted.

The current study investigates the effect of welding speed on the mechanical and microstructural properties in similar friction stir welding of Aluminium Alloy (AA-6351-T6). The contribution of intense plastic deformation and high-temperature exposure within the stirred zone during friction stir welding results in recrystallization and development of texture within the stirred zone and precipitate dissolution and coarsening within and around the stirred zone. Based on micro-structural characterization of grains and precipitates, three distinct zones, stirred (nugget) zone, thermo-mechanically affected zone (TMAZ), and heat-affected zone (HAZ).The micro-structural changes in various zones have significant effect on post weld mechanical properties.

Welding is one of the most commonly joining processes used in industry at widespread. Austenitic stainless steel are application in fabrication pressure vessels. Thin sheets of 304L can be welded by pulsed Tungsten Inert Gas (TIG) joining process. The current study investigates the numerical modelling of pulsed TIG welding of austenitic stainless steel using ANSY APDL. Double ellipsoidal heat source have been used for modelling the pulsed TIG welding. The objective of the present investigation is to study the effect of varying welding current on the temperature distribution curve. Temperature profile affects the microstructure, mechanical properties and the residual stresses developed in the welded joint during TIG welding. It has been observed that the peak temperature increases with increasing welding current.