Shock Wave Processing of Metal Powders and their Micro-structural Characterization

Sharma, Akash Deep; Sharma, Ankush; Thakur, Nagesh; Tripathi, Sushil; Dharamvir, Keya; Kumar, Ranjan; Saini, G. S. S.

doi:10.1063/1.3653638

Cited by 1 publication

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Distinctive challenges arising on the solidification/ compaction of powders are due to deterioration of fine grained structure as well as formation of undesired phases in the crystal structure that may result into weak sub-structural strengthening and poor mechanical properties. These powder metallurgical processes due to the high capital investment and extended operating period do not provide satisfactory microstructural sub-strengthening [6][7][8][9] .…”

Section: Introductionmentioning

confidence: 99%

A Constitutive Modeling and Experimental Effect of Shock Wave on the Microstructural Sub-strengthening of Granular Copper

Sharma¹,

Sharma²,

Thakur

2021

j. of met. mater. res.

Self Cite

View full text Add to dashboard Cite

Micro-sized copper powder (99.95%; O≤0.3) has been shock-processed with explosives of high detonation velocities of the order of 7.5km/s to observe the structural and microstructural sub-strengthening. Axisymmetric shock-consolidation technique has been used to obtain conglomerates of granular Cu. The technique involves the cylindrical compaction system wherein the explosive-charge is in direct proximity with the powder whereas the other uses indirect shock pressure with die-plunger geometry. Numeric simulations have been performed on with Eulerian code dynamics. The simulated results show a good agreement with the experimental observation of detonation parameters like detonation velocity, pressure, particle velocity and shock pressure in the reactive media. A pin contactor method has been utilized to calculate the detonation pressure experimentally. Wide angled x-ray diffraction studies reveal that the crystalline structure (FCC) of the shocked specimen matches with the un-shocked specimen. Field emissive scanning electron microscopic examination of the compacted specimens show a good sub-structural strengthening and complement the theoretical considerations. Laser diffraction based particle size analyzer also points towards the reduced particle size of the shock-processed specimen under high detonation velocities. Micro-hardness tests conducted under variable loads of 0.1kg, 0.05kg and 0.025kg force with diamond indenter optical micrographs indicate a high order of micro-hardness of the order of 159Hv. Nitrogen pycnometry used for the density measurement of the compacts shows that a compacted density of the order of 99.3% theoretical mean density has been achieved.

show abstract

Section: Introductionmentioning

confidence: 99%