Study of Workability Limits of Porous Materials under Different Upsetting Conditions by Compressible Rigid Plastic Finite Element Method

Zhang, X. Q.; Peng, Yinghong; Xue-yu, Ruan; Li, M. Q.; Wu, Shoujun

doi:10.1361/105994900770346114

Cited by 33 publications

(14 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The result agrees well with the findings of authors Zhang et al 2000a;Zhang et al 2000b). The barreling effect increases with increase in the tool-work piece interface friction which is due to restricted flow of metals at the interfaces.…”

Section: Effect Of Frictionsupporting

confidence: 92%

“…Lee and Kuhn (1973) developed a mathematical model based on total strain at failure to evaluate the effect of material characteristics and process parameters on the initiation of ductile fracture. Zhang et al (2000a) and Down and Kuhn (1975) investigated the fracture loci (tensile strain/compressive strain) for porous materials under various processing conditions. In addition, several authors (Vujovic and Shabaik 1986;Clift et al 1990;Ko et al 1996) developed models for predicting ductile fracture initiation during bulk metal forming.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Prediction of ductile fracture initiation for powder metallurgical aluminum-copper preforms using FEM

Wolla

Davidson

Khanra

2015

Int J Mech Mater Eng

View full text Add to dashboard Cite

Background: The deformation of Al-Cu alloys is limited to an intermediate stage due to formation of ductile fracture. The present paper deals with the investigation of the effect of process parameters on the strain paths and ductile fracture initiation of powder metallurgical (P/M) aluminum-copper preforms using FEM during metal forming. Methods: The various Al-Cu preforms were prepared using P/M route. Ductile fracture criterion based on local compressive and tensile strains in combination with FEM was employed to determine the fracture limit. Results: The fracture loci were determined by using experimental method for P/M Al, Al-2wt%Cu, Al-4wt%Cu and Al-6wt%Cu preforms. The results were analyzed for the influence of material composition, initial relative density, aspect ratio and friction on the ductile fracture initiation. The FEM simulations provided detail information on the local compressive and tensile strain paths.Conclusions: The results demonstrate that increase of copper content has decreased the plain ductility limit of the material and, hence the fracture limit decreases. In addition, the fracture limit increases with increase in the initial relative density and aspect ratio or decrease in the tool-work piece interface friction irrespective of the material composition.

show abstract

Section: Effect Of Frictionsupporting

confidence: 92%

Section: Introductionmentioning

confidence: 99%

Prediction of ductile fracture initiation for powder metallurgical aluminum-copper preforms using FEM

Wolla

Davidson

Khanra

2015

Int J Mech Mater Eng

View full text Add to dashboard Cite

show abstract

“…Aluminium alloy-graphite particulate composites (Al/Gr MMCs) exhibit improvement in mechanical properties, low friction and wear, reduced temperature rise at the wearing contact surface, excellent anti-seizure effects, improved machinability, low thermal expansion and high damping capacity because of graphite reinforcement 21 . Hybrid aluminium matrix composites are produced with the addition of solid lubricant particles such as graphite along with hard ceramic particles to improve the tribological and self-lubricating properties of the composites 22 . The main drawback of the powder metallurgy process is porosity in components after sintering.…”

Section: Introductionmentioning

confidence: 99%

Workability studies on Al+2.5%TiO2+Gr powder metallurgy composites during cold upsetting

Ravichandran¹,

Sait²,

Anandakrishnan

2014

Mat. Res.

View full text Add to dashboard Cite

Al+2.5%TiO 2 +Gr composites were synthesized through powder metallurgy technique and their workability behavior has been studied under tri-axial stress state condition. The powders were compacted using suitable punch and die in 400 kN hydraulic press and sintered at a temperature of about 590 °C for a period of 3 hours in an electric muffle furnace. The sintered preforms were characterized by XRD and SEM analysis. Then the preforms were subjected to incremental compressive loading of 10 kN until the cracks found at the free surface. The true axial stress (s z ), true hoop stress (s ө ), true hydrostatic stress (s m ) true effective stress (s eff ), formability stress index (β) and stress ratio parameters [(s z /s eff ), (s m /s eff ), (s ө /s eff )] were calculated for all the preforms and these are correlated with the true axial strain (e z ). It is inferred that, the addition of TiO 2 and Gr to the Al matrix material increases the stress ratio parameters and formability stress index (β). A hardness test was also conducted for sintered and cold forged preforms and results are reported.

show abstract

“…Since the primary cause of fracture in upsetting is the circumferential tensile stresses, it is therefore essential to investigate fracture during cold upsetting of sintered powder materials [5][6][7] . The presence of friction at the die contact surfaces directly affects the plastic deformation and is a major concern in metal forming operations.…”

Section: Introductionmentioning

confidence: 99%

Some aspects of barreling in sintered plain carbon steel powder metallurgy preforms during cold upsetting

Narayan

Ananthanarayanan

2012

Mat. Res.

View full text Add to dashboard Cite

The present research establishes a relationship of bulged diameter with densification and hydrostatic stress in forming of sintered iron (Fe) powder metallurgy preforms cold upset under two different frictional conditions, namely, nil/no and graphite lubricant condition. Sintered plain carbon steel cylindrical preforms with carbon (C) contents of 0, 0.35, 0.75 and 1.1% with constant initial theoretical density of 84% and aspect ratio of 0.4 and 0.6 were prepared using a suitable die-set assembly on a 1 MN capacity hydraulic press and sintered for 90 minutes at 1200 °C. Each sintered preform was cold upset under two different frictional constraints. It is seen that the degree of bulging reduces with reducing frictional constraints at the die contact surface. Further, it is found that the bulging ratio changed as a function of relative density and hydrostatic stress, respectively, according to the power law equations.

show abstract

Study of Workability Limits of Porous Materials under Different Upsetting Conditions by Compressible Rigid Plastic Finite Element Method

Cited by 33 publications

References 4 publications

Prediction of ductile fracture initiation for powder metallurgical aluminum-copper preforms using FEM

Prediction of ductile fracture initiation for powder metallurgical aluminum-copper preforms using FEM

Workability studies on Al+2.5%TiO2+Gr powder metallurgy composites during cold upsetting

Some aspects of barreling in sintered plain carbon steel powder metallurgy preforms during cold upsetting

Contact Info

Product

Resources

About