A STUDY ON VICKERS HARDNESS DISTRIBUTION OF MORTAR WITH SILICATE TYPE SURFACE PEMETRANTS

Al3Zr has the highest melting temperature (1580°C) among the tri-aluminide intermetal1ics. When prepared by casting, Al3Zr forms in the tetragonal DO23 structure but by rapid quenching or by mechanical alloying (MA) it can also be prepared in the metastable cubic L12 structure. The L12 structure can be stabilized to at least 1300°C by the addition of copper and other elements. We report a TEM study of the microstructure of bulk Al5CuZr2 prepared by hot pressing mechanically alloyed powder.MA was performed in a Spex 800 mixer using a hardened steel container and balls and adding hexane as a surfactant. Between 1.4 and 2.4 wt.% of the hexane decomposed during MA and was incorporated into the alloy. The mechanically alloyed powders were degassed in vacuum at 900°C. They were compacted in a ram press at 900°C into fully dense samples having Vickers hardness of 1025. TEM specimens were prepared by mechanical grinding followed by ion milling at 120 K. TEM was performed on a Philips CM30 at 300kV.

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Improve the Micro-hardness of Single Point Incremental Forming Product Using Magnetic Abrasive Finishing

Engineering and Technology Journal ◽

10.30684/etj.v38i8a.906 ◽

2020 ◽

Vol 38 (8A) ◽

pp. 1137-1142

Author(s):

Baqer A. Ahmed ◽

Saad K. Shather ◽

Wisam K. Hamdan

Keyword(s):

Vickers Hardness ◽

Feed Rate ◽

Incremental Forming ◽

Single Point ◽

Single Point Incremental Forming ◽

Step Size ◽

Coil Current ◽

Magnetic Abrasive Finishing ◽

Finishing Process ◽

Abrasive Finishing

In this paper the Magnetic Abrasive Finishing (MAF) was utilized after Single Point Incremental Forming (SPIF) process as a combined finishing process. Firstly, the Single Point Incremental forming was form the truncated cone made from low carbon steel (1008-AISI) based on Z-level tool path then the magnetic abrasive finishing process was applied on the surface of the formed product. Box-Behnken design of experiment in Minitab 17 software was used in this study. The influences of different parameters (feed rate, machining step size, coil current and spindle speed) on change in Micro-Vickers hardness were studied. The maximum and minimum change in Micro-Vickers hardness that achieved from all the experiments were (40.4 and 1.1) respectively. The contribution percent of (feed rate, machining step size, coil current and spindle speed) were (7.1, 18.068, 17.376 and 37.894) % respectively. After MAF process all the micro surface cracks that generated on the workpiece surface was completely removed from the surface.

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