Effects of lubrication in warm powder compaction process

Md Mujibur Rahman, S. S.M. Nor, H. Y. Rahman

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Warm compaction is an advanced manufacturing technique which consists of two consecutive steps, i.e. powder compaction at above ambient temperature and sintering in a controlled environment. Due to the relative movement between the powder mass and die wall as well as sliding among powder particles, frictional force is generated during the compaction stage. Admixed lubricant is used during the compaction step in order to minimize friction and hence improve the uniformity of the density of distribution inside the component. However, during the sintering process, trapped lubricant is often found to be burnt out hence leaving pores or voids which result in the lower strength of the final products. Warm compaction was initiated in the nineties, however not much information has been published about the effects of lubrication on the quality of the components produced through this route. Therefore, this paper presents the outcome of an experimental investigation about the effects of lubrication on manufacturing near-net shape components through the warm compaction route. Iron powder ASC 100.29 was mixed mechanically with zinc stearate to prepare the feedstock. Mixing time, weight percentage of lubricant content and compaction temperature were varied during green compact generation while sintering temperature, heating rate and holding time were manipulated during sintering. The relative densities and strengths of the final products were investigated at every compaction as well as sintering parameter. The results revealed that lubrication could provide significant effects at the compaction temperature of 180°C while no significant effect of lubrication was observed during sintering. The suitable lubricant content was found to be 0.4 wt% and mixing time was around 30 min and the sintering temperature was around 990°C.

Original languageEnglish
Pages (from-to)11-18
Number of pages8
JournalASM Science Journal
Volume5
Issue number1
Publication statusPublished - 08 Nov 2011

Fingerprint

Lubrication
Compaction
Powders
Sintering
Lubricants
Temperature
Iron powder
Heating rate
Feedstocks
Zinc
Friction

All Science Journal Classification (ASJC) codes

  • General

Cite this

Rahman, Md Mujibur ; Nor, S. S.M. ; Rahman, H. Y. / Effects of lubrication in warm powder compaction process. In: ASM Science Journal. 2011 ; Vol. 5, No. 1. pp. 11-18.
@article{e869512519bd4387b1b77b326452cd22,
title = "Effects of lubrication in warm powder compaction process",
abstract = "Warm compaction is an advanced manufacturing technique which consists of two consecutive steps, i.e. powder compaction at above ambient temperature and sintering in a controlled environment. Due to the relative movement between the powder mass and die wall as well as sliding among powder particles, frictional force is generated during the compaction stage. Admixed lubricant is used during the compaction step in order to minimize friction and hence improve the uniformity of the density of distribution inside the component. However, during the sintering process, trapped lubricant is often found to be burnt out hence leaving pores or voids which result in the lower strength of the final products. Warm compaction was initiated in the nineties, however not much information has been published about the effects of lubrication on the quality of the components produced through this route. Therefore, this paper presents the outcome of an experimental investigation about the effects of lubrication on manufacturing near-net shape components through the warm compaction route. Iron powder ASC 100.29 was mixed mechanically with zinc stearate to prepare the feedstock. Mixing time, weight percentage of lubricant content and compaction temperature were varied during green compact generation while sintering temperature, heating rate and holding time were manipulated during sintering. The relative densities and strengths of the final products were investigated at every compaction as well as sintering parameter. The results revealed that lubrication could provide significant effects at the compaction temperature of 180°C while no significant effect of lubrication was observed during sintering. The suitable lubricant content was found to be 0.4 wt{\%} and mixing time was around 30 min and the sintering temperature was around 990°C.",
author = "Rahman, {Md Mujibur} and Nor, {S. S.M.} and Rahman, {H. Y.}",
year = "2011",
month = "11",
day = "8",
language = "English",
volume = "5",
pages = "11--18",
journal = "ASM Science Journal",
issn = "1823-6782",
publisher = "Akademi Sains Malaysia",
number = "1",

}

Rahman, MM, Nor, SSM & Rahman, HY 2011, 'Effects of lubrication in warm powder compaction process', ASM Science Journal, vol. 5, no. 1, pp. 11-18.

Effects of lubrication in warm powder compaction process. / Rahman, Md Mujibur; Nor, S. S.M.; Rahman, H. Y.

In: ASM Science Journal, Vol. 5, No. 1, 08.11.2011, p. 11-18.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Effects of lubrication in warm powder compaction process

AU - Rahman, Md Mujibur

AU - Nor, S. S.M.

AU - Rahman, H. Y.

PY - 2011/11/8

Y1 - 2011/11/8

N2 - Warm compaction is an advanced manufacturing technique which consists of two consecutive steps, i.e. powder compaction at above ambient temperature and sintering in a controlled environment. Due to the relative movement between the powder mass and die wall as well as sliding among powder particles, frictional force is generated during the compaction stage. Admixed lubricant is used during the compaction step in order to minimize friction and hence improve the uniformity of the density of distribution inside the component. However, during the sintering process, trapped lubricant is often found to be burnt out hence leaving pores or voids which result in the lower strength of the final products. Warm compaction was initiated in the nineties, however not much information has been published about the effects of lubrication on the quality of the components produced through this route. Therefore, this paper presents the outcome of an experimental investigation about the effects of lubrication on manufacturing near-net shape components through the warm compaction route. Iron powder ASC 100.29 was mixed mechanically with zinc stearate to prepare the feedstock. Mixing time, weight percentage of lubricant content and compaction temperature were varied during green compact generation while sintering temperature, heating rate and holding time were manipulated during sintering. The relative densities and strengths of the final products were investigated at every compaction as well as sintering parameter. The results revealed that lubrication could provide significant effects at the compaction temperature of 180°C while no significant effect of lubrication was observed during sintering. The suitable lubricant content was found to be 0.4 wt% and mixing time was around 30 min and the sintering temperature was around 990°C.

AB - Warm compaction is an advanced manufacturing technique which consists of two consecutive steps, i.e. powder compaction at above ambient temperature and sintering in a controlled environment. Due to the relative movement between the powder mass and die wall as well as sliding among powder particles, frictional force is generated during the compaction stage. Admixed lubricant is used during the compaction step in order to minimize friction and hence improve the uniformity of the density of distribution inside the component. However, during the sintering process, trapped lubricant is often found to be burnt out hence leaving pores or voids which result in the lower strength of the final products. Warm compaction was initiated in the nineties, however not much information has been published about the effects of lubrication on the quality of the components produced through this route. Therefore, this paper presents the outcome of an experimental investigation about the effects of lubrication on manufacturing near-net shape components through the warm compaction route. Iron powder ASC 100.29 was mixed mechanically with zinc stearate to prepare the feedstock. Mixing time, weight percentage of lubricant content and compaction temperature were varied during green compact generation while sintering temperature, heating rate and holding time were manipulated during sintering. The relative densities and strengths of the final products were investigated at every compaction as well as sintering parameter. The results revealed that lubrication could provide significant effects at the compaction temperature of 180°C while no significant effect of lubrication was observed during sintering. The suitable lubricant content was found to be 0.4 wt% and mixing time was around 30 min and the sintering temperature was around 990°C.

UR - http://www.scopus.com/inward/record.url?scp=80355140868&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=80355140868&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:80355140868

VL - 5

SP - 11

EP - 18

JO - ASM Science Journal

JF - ASM Science Journal

SN - 1823-6782

IS - 1

ER -