The Effect On Microstructure Mechanical Properties Of Vanadıim In Nb-V Microalloyed Steel Produced By Powder Metallurgy

Year 2018, Volume:6 No:3 (2018) (Special Issue: UMAS 2017), 629 - 636, 10.04.2018

Mehmet Akif Erden , Samet Barlak Berkay Adalı Özgür Çelikkıran

Abstract

In this study, the addition of vanadium element (0-0,025-0,05-0,1-0,3-0,5-1-3% by weight) at different ratios as well as the addition of graphite and niobium in the fixed matrix into the Fe matrix by powder metallurgy method the steel material in the composition is obtained as a powder mixture. The obtained powders were compacted at 700 MPa pressing pressure in the form of drawn specimen and steel production was performed by sintering at 1400 ° C in argon atmosphere in an atmosphere controlled tube furnace. The mechanical properties of Nb-V microalloyed steel specimens with different V ratios were analyzed by tensile and microhardness test. Microstructure of powder metal steels is characterized by optical microscope. The results show that the TM steel
samples added with 1% V by weight have the highest yield and tensile strength. With increasing the V content from 1% to 3%, a decrease in yield and tensile strength was observed.

Keywords

Powder metallurgy, Nb-V Microalloyed Stell, V, Micro structure, Tensile strength

Toz Metalurjisi İle Üretilen Nb-V Mikroalaşim Çeliğine Vanadyum İlavesinin Mikroyapi Mekaniksel Özellikleri Üzerine Etkisi

Abstract

Bu çalışmada toz
metalurjisi yöntemiyle Fe matris içerisine sabit oranda grafit ve niyobium
ilavesinin yanı sıra farklı oranlarda vanadyum elementinin (% Ağırlık olarak
0-0,025-0,05-0,1-0,3-0,5-1-3) katılmasıyla istenilen bileşimde çelik malzeme
toz karışım olarak elde edilmiştir. Elde edilen tozlar çekme numunesi şeklinde
tasarlanan kalıpta 700 MPa presleme basıncında sıkıştırılarak atmosfer
kontrollü tüp fırında argon atmosferinde 1400ͦC’de sinterlenerek çelik üretimi
gerçekleştirilmiştir. Farklı V oranlarına sahip Nb-V mikroalaşımlı çelik
numunelerin mekanik özellikleri çekme ve mikrosertlik testi ile analiz
edilmiştir. Toz metal çeliklerin mikroyapısı optik mikroskop ile karakterize
edilmiştir. Sonuçlar % ağırlık olarak % 1 V ilave edilmiş TM çelik numunelerin
en yüksek akma ve çekme dayanımına sahip olduğu göstermektedir.  V miktarı %1’dan %3’e çıkması ile akma ve
çekme dayanımında azalma gözlenmiştir.

Keywords

Toz metalürjisi, Nb-V mikroalaşımlı çelikler, Mikroyapı, Mekanik Özellikler

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