Wear and friction performance under lubricated reciprocating tests of steel powder mixtures sintered by Spark Plasma Sintering

Boidi, G.; Fukumasu, Newton Kiyoshi; Machado, Izabel Fernanda

doi:10.1016/j.triboint.2018.01.032

Cited by 16 publications

(18 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Main results showed that high porosity decrease elastic properties and surface load support capacity, causing excessive wear and closure of local pores [114]. Surface pore collapse avoids any beneficial effect on lubrication, as previously found by Boidi and co-authors [19,22]. Furthermore, Ebner and co-authors [113] verified that close porosity could improve lubrication rather than open one (connected network of pores).…”

Section: Tribological Effect Of Surface Porosity In Pm Materialssupporting

confidence: 56%

“…3 The essential information for understanding the research was reported here, and complementarily the main results obtained has been already published elsewhere [18][19][20][21][22][23].…”

Section: Research Questionsmentioning

confidence: 65%

“…The application of an external electric field influenced the movement of crystalline defects, nucleation and crystal growth, evaporation and oxidation processes, as reported by Chen et al [30]. The SPS process is a variation of the electric field applied technique and has attracted considerable attention [19,22,[31][32][33].…”

Section: Spark Plasma Sintering (Sps) Techniquementioning

confidence: 94%

“…Porosity characterization of PM materials plays a crucial role, since pores significantly influence mechanical and tribological properties [11,14,16,19,60].…”

Section: Porosity and Pore Morphology Measurementsmentioning

confidence: 99%

“…Some types of additives could be activated at high contact pressure (Extreme pressure -EP). Contact pressure is higher when using limited contact area, therefore EP additives are generally first activated on asperities peaks on rough surfaces, rather than smooth ones [19]. Surface features directionality also represents a key factor to be analysed when using additives [91].…”

Section: Tribological Effect Of Surface Topographymentioning

confidence: 99%

See 4 more Smart Citations

An experimental assessment of surface micro irregularities (porosity and texture) effects on tribological behaviour under lubricated conditions.

Boidi¹

View full text Add to dashboard Cite

recent years, although this procedure usually implies extra manufacturing operations and costs. On the other hand, sintered materials contain themselves surface cavities that could potentially act as surface texture and, consequently, lead to friction reduction. This research aims to extend the current knowledge on the tribological influence of micro surface irregularities (pores and laser texture) under lubricated experimental tests and explore the use of these features for tribological applications. Samples were manufactured using both sintering and texturing processes to obtain different surface characteristics. Three different porosity conditions were produced for sintered steels, whereas grooves and dimples configurations were designed for textured steel samples. After that, experimental tests were performed under varying sliding-rolling conditions (from prevalent rolling to prevalent sliding) especially using non-conformal contact. Speed was also varied during frictional tests to cover a wide range of operational conditions and verify the effects of surface features under different lubrication regimes. Friction tests were carried out with two tribometers using configurations of pin-on-disk, roller-on-disk and ball-on-disk. Film thickness was measured by an ultra-thin optical interferometry rig using a methodology properly designed for rough samples. Samples with smooth surfaces were utilized as a reference bench to be compared to material with surface modification (texture or porosity). Main results showed that the decrease of porosity led to friction reduction in the sintered steel. Material with reduced porosity performed even better than reference smooth samples. In addition, the dimple configuration promoted friction reduction, whereas grooves generally performed similarly or worse than reference material. Even if textured dimples and small porosity on sintered material were produced by different techniques, they presented similar geometrical characteristics and consequently they both reduced friction compared to reference samples. As part of the outcome, main results were mapped to better understand the effect of each surface feature on tribological performance. Furthermore, a preliminary phenomenological model was proposed to predict frictional response of surface with micro cavities (pores or texture) from reference steel results. Main findings suggest that the effect of tailored surface cavities could be somehow compared to randomly distributed ones, even if produced by very different manufacturing techniques.

show abstract

Section: Tribological Effect Of Surface Porosity In Pm Materialssupporting

confidence: 56%

“…3 The essential information for understanding the research was reported here, and complementarily the main results obtained has been already published elsewhere [18][19][20][21][22][23].…”

Section: Research Questionsmentioning

confidence: 65%

Section: Spark Plasma Sintering (Sps) Techniquementioning

confidence: 94%

“…Porosity characterization of PM materials plays a crucial role, since pores significantly influence mechanical and tribological properties [11,14,16,19,60].…”

Section: Porosity and Pore Morphology Measurementsmentioning

confidence: 99%

Section: Tribological Effect Of Surface Topographymentioning

confidence: 99%

See 3 more Smart Citations