Naslov
ANALYSIS OF THE INFLUENCE OF THERMOCHEMICAL TREATMENT ON STRUCTURE AND MECHANICAL PROPERTIES OF STEEL 20MnCr5

Autori
Marušić, Vlatko ; Rosandić, Željko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
20th JUBILEE CONFERENCE ON MATERIALS AND TECHNOLOGY / Godec, Matjaž ; Donik, Črtomir, Paulin, Irena ; Kocijan, Aleksandra - Ljubljana : Inštitut za kovinske materiale in tehnologije, Ljubljana, 2012, 107-107

Skup
Inštitut za kovinske materiale in tehnologije, Ljubljana, Lepi pot 11, Ljubljana, Slovenija

Mjesto i datum
Portorož, Slovenija, 17.10.2012. - 19.10.2012

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
: thermochemical treatment; fracture surface; micro-structure; mechanical properties

Sažetak
In operation, the gear pumps are exposed to elevated pressures and temperatures. They allow the circulation of heated raw material in the injection molding machines for plastics. In one of these pumps, frequent downtime occurred due to the fracture of drive gear. The gears installed as the standard spare parts lasted only three months in operation. Metallographic testing was performed on the fractured standard gear (Figure 1). The hardness of the cross-section and the surface was tested. The effective depth of the cemented layer was determined. The fracture surface was examined. The chemical analysis of the material was performed. Based on the analysis of results, it was determined that high hardenability of steel was the most probable cause for the fracture of standard gear. Based on these results, and with the goal to extend the life of gear, 2 test gears were made of the case hardening steel 20MnCr5. Significant life extension of gear was achieved. The test gears were in operation for nine months after installation. The fracture of the test gear occurred in the same area as with the standard gear (Figure 2). The testing, which was used on the standard gear that lasted only three months in operation, was performed also on the test gear.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo

POVEZANOST RADA