Showing papers in "Technological Applied Sciences in 2020"
TL;DR: In this article, the effect of different sintering time (1h, 2h and 3h) on the tensile strength of powder metallurgy (PM) plain carbon steel and microalloyed steels with different amount of niobium and vanadium content (0-0.2 wt%) were investigated.
Abstract: Microalloyed steels can be defined as low alloyed high strength steels which increase the strength of steel by mechanisms such as precipitation hardening, aggregation hardening, particle size reduction, dispersion hardening by adding microalloy elements such as aluminium, niobium, vanadium and titanium in the range of 0.05% and 0.20%. Powder metallurgy is one of the manufacturing methods in which small parts which are difficult to manufacture can be produced in series with some parts which are close to the final shape with minimum material loss and which cannot be produced by other production methods. In this work, effect of different sintering time (1h., 2h. and 3h.) on the tensile strength of powder metallurgy (PM) plain carbon steel and microalloyed steels with different amount of niobium and vanadium content (0-0.1-0.2 wt%) were investigated. As a result, it was determined that the added alloying elements increased the mechanical properties. 0.2 wt % Nb-V added and sintered 2 h. PM steel showed the highest values in yield strength (YS), ultimate tensile strength (UTS).
5 citations
Abstract: This study aims to investigate corrosion properties of Ti-B 4 C/CNF functional graded materials (FGMs). FGMs are produced in three layers by traditional cold pressing and sintering method. While B 4 C was incorporated into the Ti matrix at 5%, 10% and 15% percent, the CNF was only 0.5% by volume. Corrosion properties of FGMs are determined by potentiodynamic method. 3 M HCl was preferred as the corrosion solution. Corrosion rates were calculated from the Tafel curve and the corrosion surface was examined by using SEM-EDS. The results show that the corrosion process of composite material in 3 M HCl showed different corrosion resistance, in which corrosion rate showed the evolution trend of initial increase and subsequent decrease, while amount of reinforcement changed. While the best corrosion resistance among the FGMs was determined in the sample with 5%B 4 C additive, the worst corrosion resistance was determined with 15%B 4 C+0.5% CNF additive.
3 citations
Journal Article•
TL;DR: Kaplama islemleri, asinmaya maruz kalan is parcalarinin korunmasi ve calisma omrunun uzatilmasi acisindan etkili bir cozumdur as mentioned in this paper.
Abstract: Kaplama islemleri, asinmaya maruz kalan is parcalarinin korunmasi ve calisma omrunun uzatilmasi acisindan etkili bir cozumdur. Bu calismada; DKP celik, AISI 310 ve AISI 430 paslanmaz celik altlik malzemeler uzerine WC tozlari termal sprey kaplama yontemlerinden biri olan yuksek hizda oksi yakit puskurtme (HVOF) yontemiyle 100-200 µm araliginda kaplama kalinligina sahip olacak sekilde kaplamalar uretilmistir. Kaplamalara; kalinlik olcumu, sertlik testi, stereo mikroskop incelemeleri ve pin-on disk asinma testleri uygulanmistir. Asinma testi sonucunda olusan hacimsel kayiplar, puruzluluk test cihazindan elde edilen asinma iz derinliklerine gore hesaplanmistir. Sonuc olarak, WC tozu ile kaplanmis AISI 310 paslanmaz celik altlik malzemesinin asinma direncinin diger numunelere gore daha fazla oldugu tespit edilmistir.
1 citations