Abstract
The investigation was performed on pure sintered (PM) copper and dilute PM copper-based alloys with 3 and 5.9 wt.% of platinum. Investigated PM samples were obtained using the standard powder metallurgy technique by mixing the elemental powders in proper ratio followed by pressing in hydraulic press and sintering in a hydrogen atmosphere. The PM samples were further cold deformed by rolling at ambient temperature to a total rolling reduction of 60 %. On pre-deformed samples, the low-temperature isothermal annealing up to the 100 hours was accomplished. During all stages of isothermal annealing, the values of Vickers hardness, micro-hardness, and electrical conductivity were measured. Also, the microstructure was analyzed using the scanning electron microscopy (SEM). This investigation has shown a slight increase in all measured properties for both dilute Cu-Pt alloys. An increase in mechanical properties was some more pronounced for more alloyed Cu-5.9wt%Pt alloy. During the low-temperature isothermal annealing, there were no significant changes in properties for pure pre-deformed copper.
Highlights
Priprema uzoraka za metalografsko ispitivanje podrazumevala je brušenje, mehaničko poliranje i nagrizanje
During the low-temperature isothermal annealing, there were no significant changes in properties for pure predeformed copper
Summary
U ovom eksperimentalnom istraživanju korišćeni su kao polazni materijali elektrolitički bakarni prah čistoće 99,7 % i prah platine čistoće 99,92 %. Mešanje je trajalo 2 h u cilju dobijanja homogene mešavine prahova sastava Cu-3 tež.%Pt i Cu-5,9 tež.%Pt. Otpresci od tako dobijenih mešavina prahova, kao i otpresci od čistog bakra, u cilju upoređenja osobina, pripremljeni su u obliku pravougaonih prizmatičnih komada dimenzija 30 mm × 12 mm×7 mm, korišćenjem jednoosnog presovanja. Nakon oblikovanja na sobnoj temperature otpresci su sinterovani u cevnoj peći tipa „T40/600“ na temperaturi od 810°C u trajanju od 1,5 h u atmosferi čistog protočnog vodonika. Tokom različitih stadijuma izotermalnog žarenja merene su vrednosti tvrdoće i mikrotvrdoće po Vikersu, kao i vrednosti električne provodnosti. Tvrdoća je merena primenom „VEB Leipzig“ uređaja za merenje tvrdoće. Mikrotvrdoća je merena pomoću uređaja za merenje mikrotvrdoće „PMT-3“. Za merenje vrednosti električne provodnosti ispitivanih uzoraka korišćen je uređaj „Sigmatest 2.063“. Priprema uzoraka za metalografsko ispitivanje podrazumevala je brušenje, mehaničko poliranje i nagrizanje
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
