TY - BOOK

T1 - High temperature abrasion in sinter plants and their cost efficient wear protection

AU - Varga, Markus

N1 - no embargo

PY - 2016

Y1 - 2016

N2 - Abrasive wear at high temperatures (HT) is a serious issue in many industrial applications. Within this work, on the example of an iron ore sinter plant, maintenance tasks were analysed and abrasive wear was found to be the most frequent tribological failure. Core components like the grate bars of the sinter belt, the sinter crusher system and the hot sieve suffer from abrasion at HT, with various forms of abrasion present. Failure analysis pointed out that high-stress abrasion, impact-abrasion and erosion are of major concern, hence these abrasion modes were studied in detail at temperatures up to 550°C-700°C. The influence of the various forms of abrasion on prospective HT wear-resistant materials was investigated. Relative soft cast materials with low amount of hardphases (40 %) and high hardness at application temperature are necessary to withstand impact-abrasion, because low hardphase containing materials showed up to 17× higher wear loss. MML formation is strongly dependent on the microstructure of the material: hardfacings with more than 40 % hardphases do not show significant MML formation. Temperature-induced material softening and severe abrasive contact encourage massive MML formation on low hardphase containing materials. In this case, wear protection of in-situ formation of MML was pronounced at HT. Linear correlation of abrasive wear rates with hot hardness was especially evident at high-stress abrasion and oblique erosion (30°). Further, the ratio of normal and oblique erosion follows a linear relationship with the hot hardness for nearly all materials and temperatures investigated.

AB - Abrasive wear at high temperatures (HT) is a serious issue in many industrial applications. Within this work, on the example of an iron ore sinter plant, maintenance tasks were analysed and abrasive wear was found to be the most frequent tribological failure. Core components like the grate bars of the sinter belt, the sinter crusher system and the hot sieve suffer from abrasion at HT, with various forms of abrasion present. Failure analysis pointed out that high-stress abrasion, impact-abrasion and erosion are of major concern, hence these abrasion modes were studied in detail at temperatures up to 550°C-700°C. The influence of the various forms of abrasion on prospective HT wear-resistant materials was investigated. Relative soft cast materials with low amount of hardphases (40 %) and high hardness at application temperature are necessary to withstand impact-abrasion, because low hardphase containing materials showed up to 17× higher wear loss. MML formation is strongly dependent on the microstructure of the material: hardfacings with more than 40 % hardphases do not show significant MML formation. Temperature-induced material softening and severe abrasive contact encourage massive MML formation on low hardphase containing materials. In this case, wear protection of in-situ formation of MML was pronounced at HT. Linear correlation of abrasive wear rates with hot hardness was especially evident at high-stress abrasion and oblique erosion (30°). Further, the ratio of normal and oblique erosion follows a linear relationship with the hot hardness for nearly all materials and temperatures investigated.

KW - tribology

KW - abrasion

KW - high temperature

KW - hardfacing

KW - sinter plant

KW - maintenance

KW - Tribologie

KW - Abrasion

KW - Hochtemperatur

KW - Hartauftragung

KW - Sinteranlage

KW - Instandhaltung

M3 - Doctoral Thesis

ER -