Experimental investigations of grain size effects in forward microextrusion

Rajenthirakumar, D.; Sridhar, R.; Abenethiri, R.; Kartik, R.; Bagri, Dwarkesh

doi:10.1007/s00170-015-7497-0

Cited by 12 publications

(10 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Because these grain boundaries acts as a barrier for slip transfer as it produces hindrance to the dislocation movement and thus resulting in pile-up dislocations which increases the strength and thereby increases the ductility. A similar trend is observed in the work of Rajenthirakumar and Sridhar [1]. Copper with extremely fine grains requires a large deformation load compared to coarse grain.…”

Section: Resultssupporting

confidence: 86%

See 1 more Smart Citation

Influence of grain size on deformational behavior in microextrusion process

Nanthakumar

Rajenthirakumar

2019

J Braz. Soc. Mech. Sci. Eng.

Self Cite

View full text Add to dashboard Cite

Miniaturization drives the need for developing appropriate technology for microproducts of extremely small geometric features with high tolerances. In this work, the authors have investigated the material behavior and size effect in microextrusion of pure copper and aluminum with different grain sizes. A forward microextrusion assembly has been developed in the first phase of work to investigate the grain size effects. The experimental results are then compared to finite element simulation to quantify force displacement response. It has been found that the simulated deformation load is comparable with experimental results. The influence of size effect in both copper and aluminum showed that the extrusion load and average microhardness of 38 μm and 34 μm are higher when compared to 204 μm and 124 μm. In the second phase of work, an attempt has been made to fabricate the copper microgear (m = 0.416 mm) by the developed extrusion setup. The findings of this work are essential for further development of micro-formed parts and will facilitate in introducing microextrusion for mass production of industrial components.

show abstract

Section: Resultssupporting

confidence: 86%

“…Understanding the material behavior and deformation behavior, relevant properties in microforming process are critical in predicting the quality of the microparts. A comprehensive work on force displacement response for microextrusion with materials of different grain sizes was carried out by Rajenthirakumar and Sridhar [1].…”

Section: Introductionmentioning

confidence: 99%

Influence of grain size on deformational behavior in microextrusion process

Nanthakumar

Rajenthirakumar

2019

J Braz. Soc. Mech. Sci. Eng.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The role of subgrains larger than the specimen diameter contributed to a reduced flow stress in the micro-compression tests [28]. In the micro-extrusion of both copper and aluminum alloys, the flow stress decreased along with the surface grain [29]. If the cavity width in micro-coining consisted of only one grain, the grain would be fragmented into smaller sizes along the extrusion direction [30].…”

Section: Introductionmentioning

confidence: 99%

Finite Element Analysis of Grain Size Effects on Curvature in Micro-Extrusion

et al. 2020

View full text Add to dashboard Cite

The precision and accuracy of the final geometry in micro-parts is crucial, particularly for high-value-added metallic products. Micro-extrusion is one of the most promising processes for delivering high-precision micro-parts. The curving tendency observed in micro-extrusion parts is a major concern, significantly affecting the final part geometry. The purpose of this paper was to investigate the driving mechanism behind the curvature in micro-extrusion at room temperature. A finite element (FE) simulation was carried out to observe the influential primary factors: (1) grain size, (2) grain boundary, (3) grain orientation, and (4) bearing length of a 6063 aluminum alloy. The Extrusion Curvature Index (ECI) was also established to indicate the level of curvature in micro-extruded parts. The results showed that the grain boundary at the high strain and die opening area was the dominant factor for single-grain conditions. The interactive effects of the grain boundary and grain orientation also affected the curvature under single-grain conditions. If the number of grains across the specimen increased up to 2.7 (poly-grains), the curvature effect was dramatically reduced (the pins were straightened). For all conditions, the curvature in micro-extrusion could be eliminated by extending the bearing length up to the exit diameter length.

show abstract

“…1 mm [9]. The most frequently considered scale effects are: the volume effect -usually combined with the size of the material grain [10,11,12] and the surface effect [5] -associated with the surface layer. The first has an impact on the quality and performance of the micro-parts, and the second on contact phenomena such as friction [13] and the tendency to adhesive bonding [14].…”

Section: Introductionmentioning

confidence: 99%