An attempt has been made to investigate the machinability of zirconia toughened alumina (ZTA) inserts while turning AISI 4340 steel. The insert was prepared by powder metallurgy process route and the machining experiments were performed based on Response Surface Methodology (RSM) design called Central Composite Design (CCD). The mathematical model of flank wear, cutting force and surface roughn...

In this work, AISI 4340 steel was produced by powder metallurgy. Samples were sintered at 1150?C for 90 min. and then cooled in the furnace. Except to those as-sintered condition, one of samples homogenized 1 h air. Other deformed temperature range 1150-930?C deformation rate 30 60% followed cooling sand, air water mediums. The grain size gradually decreased depending on or steel. Small grains ...

During quenching heat treatment, the formation of high residual stress values and presence distortion are phenomena which difficult to control accurately predict, their effects being extremely important components or pieces complex robust geometry that commonly used in industry. The latter is mainly due mixture temperature levels formed between surface cores martensitic transformation during qu...

In high-strength steels it is often difficult to distinguish between hydrogen embrittlement and various other brittle failure mechanisms. The objective of this work was to develop a sensitive analytical procedure based on secondary ion mass spectrometry (SIMS) that would allow in-service identification of local hydrogen accumulation, either during quality control or during failure analysis of e...

High speed machining (HSM) may produces parts with substantially higher fatigue strength; increased subsurface micro-hardness and plastic deformation, mostly due to the ploughing of the round cutting tool edge associated with induced stresses, and can have far more superior surface properties than surfaces generated by grinding and polishing. Cutting edge roundness may induce stress and tempera...