다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Elements Of X Ray Diffraction

Welding Metallurgy of

Welding of dissimilar magnesium alloys and aluminum alloys is an important issue because of their increasing applications in industries. In this document, the research and progress of a variety of welding techniques for joining dissimilar Mg alloys and Al alloys are reviewed from different perspectives. Welding of dissimilar Mg and Al is challenging due to the formation of brittle intermetallic compound (IMC) such as Mg17Al12 and Mg2Al3. In order to increase the joint strength, three main research approaches were used to eliminate or reduce the Mg-Al intermetallic reaction layer. First, solid state welding techniques which have a low welding temperature were used to reduce the IMCs. Second, IMC variety and distribution were controlled to avoid the degradation of the joining strength in fusion welding. Third, techniques which have relatively controllable reaction time and energy were used to eliminate the IMCs. Some important processing parameters and their effects on weld quality are discussed, and the microstructure and metallurgical reaction are described. Mechanical properties of welds such as hardness, tensile, shear and fatigue strength are discussed. The aim of the report is to review the recent progress in the welding of dissimilar Mg and Al to provide a basis for follow-up research.

A Review of Dissimilar Welding Techniques for Magnesium Alloys to Aluminum Alloys.

Some studies on P91 steel and their weldments

Characterization of as-welded microstructure of heat-affected zone in modified 9Cr–1Mo–V–Nb steel weldment

An investigation on diffusion bonding of aluminum and magnesium using a Ni interlayer

Microstructure and mechanical properties of Al-7075/B4C composites fabricated by plasma activated sintering

Mg and Al were joined through diffusion bonding using a silver interlayer film prepared by magnetron sputtering. The interfacial microstructure and mechanical performance of Mg/Al joints were greatly improved in the presence of the silver interlayer, which prevented the formation of brittle Mg–Al compounds. The typical microstructure at the joint interface is a Mg/Mg 3 Ag/MgAg/Al multilayer structure. The bonding temperature and holding time were optimized to avoid the formation of Mg–Al compounds. At low bonding temperatures (380–420 °C) and short holding times (15–45 min), the Mg–Al intermetallic compounds were eliminated owing to the presence of Mg–Ag compounds. The thicknesses of the Mg 3 Ag and MgAg layers increased with increasing temperature and longer holding times. The addition of the silver interlayer greatly improved the shear strength of the joints. The maximum microhardness of the interface compounds decreased from 368 HV to 125 HV owing to the absence of Mg–Al compounds. Fractures in the joints occurred between Mg 3 Ag/MgAg, MgAg/Al boundaries and within the inner Mg–Al layers. The fracture features differed depending on whether Mg–Al compounds were present.

Microstructure and mechanical properties of diffusion-bonded Mg–Al joints using silver film as interlayer

Effect of Al thin film and Ni foil interlayer on diffusion bonded Mg–Al dissimilar joints

Yiyu Wang

Papers

Characterization of as-welded microstructure of heat-affected zone in modified 9Cr–1Mo–V–Nb steel weldment

An investigation on diffusion bonding of aluminum and magnesium using a Ni interlayer

Microstructure and mechanical properties of Al-7075/B4C composites fabricated by plasma activated sintering

Microstructure and mechanical properties of diffusion-bonded Mg–Al joints using silver film as interlayer

Effect of Al thin film and Ni foil interlayer on diffusion bonded Mg–Al dissimilar joints