In this study superalloys, their

Rubber has become an indispensable material for the technological development of civilization, including simple balloon and complex rocket propellant. Rubber Industry worldwide is using on an average 50% of raw materials. These materials were mostly petroleum-based, except natural rubber (NR), steel cord and bead wire. Using of these petroleum-based raw materials not only depletes natural resources, but also produces more extreme environmental hazards. The waste tire rubber problem is of great magnitude and has far reaching environmental and economic implications. There are some ways for recycling of rubber, such as reclaiming technology, surface treatment, grinding and pulverization technology, devulcanization technology. Methods of devulcanizing rubber (or elastomers) have been researched almost since the time of the discovery of the rubber/sulfur vulcanization process. By devulcanization process the cross-links in the structure of rubber are broken and devulcanized rubber can be revulcanized into a raw material for rubber industry, which is a highly valued form of waste rubber. This study provides a review of the recent advances in understanding of methods of recycling rubber and claims that the capacity of thermomechanical and mechanochemical devulcanization methods of recycling waste tire rubber can be improved in future studies.

In this study solid state welding andapplication in aeronautic industryhave been researched. The solid state welding technicisused in the industrial production fields such as aircraft, nucleer, space industry, aeronautic industry, ect., actually solid state welding is a process by which similar and dissmilar metals can be bonded together. Hence a material can be created as not heavy but strong strength. Beside, advantages and disasvantages of solid state welding have been discussed. Also the diffusion welding and friction welding which belong to the solid state welding is obsevered in aeronautic industry.

During the last few years ultrasonic welding has become significant attention regarding its suitable applications in comparison to traditional welding techniques. Bonding of dissimilar materials has always been a challenging task due to poor control on grain size and sensitive mechanical properties that could have been made by joining with traditional welding techniques. Moreover, joining dissimilar materials such as Aluminum/steel, metal/glass, Aluminum/copper had not been achieved without the usage of ultrasonic welding technique. This work presents a review of literature regarding the usage of ultrasonic welding technique in many applications. Additionally, this paper provides different examples and applications of ultrasonic welding technique and its application. Main advantages of this technique are, clean and undamaged exterior parts of weld, power savings, stable and strong bond, time efficiency

Purpose The purpose of this paper is to review and examine three of the most common corrosion characterization techniques specifically on Sn-Zn solders. The discussion will highlight the configurations and recent developments on each of the compiled characterization techniques of potentiodynamic polarization, potentiostatic polarization and electrochemical impedance spectroscopy (EIS). Design/methodology/approach The approach will incorporate a literature review of previous works related to the experimental setups and common parameters. Findings The potentiostatic polarization, potentiodynamic polarization and EIS were found to provide crucial and vital information on the corrosion properties of Sn-Zn solders. Accordingly, this solder relies heavily on the amount of Zn available because of the inability to produce the intermetallic compound in between the elements. Further, the excellent mechanical properties and low melting temperature of the Sn-Zn solder is undeniable, however, the limitations regarding corrosion resistance present opportunities in furthering research in this field to identify improvements. This is to ensure that the corrosion performance can be aligned with the outstanding mechanical properties. The review also identified and summarized the advantages, recent trends and important findings in this field. Originality/value The unique challenges and future research directions regarding corrosion measurement in Sn-Zn solders were shown to highlight the rarely discussed risks and problems in the reliability of lead-free soldering. Many prior reviews have been undertaken of the Sn-Zn system, but limited studies have investigated the corrosive properties. Therefore, this review focuses on the corrosive characterizations of the Sn-Zn alloy system.