The crystallization kinetics of an Al89La6Ni5 amorphous alloy were studied by thermal analysis. Both continuous heating and isothermal DSC traces showed that the Al89La6Ni5 amorphous alloy undergoes a two-stage crystallization process upon heating. The ®rst transformation, in which fcc-Al precipitates from the amorphous matrix, is a nucleation and three-dimensional di€usion-controlled growth pr...

A new kind of decagonal quasicrystal (DQC) with a periodicity of 1.23 nm was observed in the as-cast quaternary Al60Cr20Fe10Si10 alloy. The intensity distribution of some spots in the selected-area electron diffraction pattern along the tenfold zone axis was found to be different from other Al-based DQCs. High-angle annular dark-field scanning transmission electron microscopy was adopted to rev...

In the present investigation, an attempt has been made to use “exponential model” in the prediction of fatigue life without integrating the fatigue crack growth rate curve (FCGR). The obtained results are compared with experimental crack growth data obtained for 2024-T351 aluminum alloy for four bending V-Charpy specimens under constant amplitude loading in stress ratio range from 0.1 to 0.3 an...

in hot dip galvanizing, several parameters such as chemical composition of coating bath, immersion time and surface roughness of specimens could affect microstructure and properties of coating. in this article, the effect of aluminum content, immersion time and surface roughness on structure and properties of alloy layers have been investigated. specimens of low carbon silicon-free steel with d...

This paper presents an investigation on the microstructure and property of 4043 Al-alloy parts built using a novel layer-deposition technique based on a variable polarity gas tungsten arc welding (VP-GTAW) process. Processing parameters strongly affect the geometry, microstructures, roughness, and hardness of a deposited part. A hollow cylindrical part with 120 layers is built up with a good su...

This paper describes damping capac i t y and mechanical p roper t ies o f Zn-8-20%A1 and Zn-8-20%Al-0.02-0.04XMg a l l o y cast ings. Zn-8-20%A1 a l l o y casti ngs show h igh damping when quenched from 573K. Small amount o f Mg a d d i t i o n t o these a l l o y cast ings lowers damping capaci ty considerably b u t e f f e c t i v e t o reduce decomposition through aging a t 423K f o r 48hrs ...

Self-healing alloys are promising materials that can decrease the consequences of accidents. To detect crack formation in a material is simple task that can be performed by e.g., sonic or ultrasound detection, but it is not always possible to immediately replace the damaged parts. In this situation, it is very advantageous to have the chance to heal the crack during operation, which can be done...

where the specimens are recovered but not recrystallized. This second type of yielding is characterized by a sharp yield drop and long yield elongation. A mechanism of the second type of yielding has not been investigated, but it is clear that the yielding phenomenon is not due to a simple effect of strain aging, because the specimens has recovered so that dislocation arrangements should have c...

9 The α α phase separation kinetics in a commercial Fe-20 wt% Cr-6% Al oxide dispersion-strengthened PM 1

Disks of commercial Al-1050 and ZK60A alloys were stacked together and then processed by conventional high-pressure torsion (HPT) through 1 and 5 turns at room temperature to investigate the synthesis of an Al–Mg alloy system. Measurements of microhardness and observations of the microstructures and local compositions after processing through 5 turns revealed the formation of an ultrafine multi...