SEARCH RESULT

Machining of many polycrystalline shape memory alloys CoNiAl (SMA) has been considerably a new phenomenon. CoNiAl alloys should be made available for final use after being formed, without loss of their shape memory properties. In this study, the effect of cutting parameters on kerf width and dimension tolerance of the Co based Shape Memory Alloy (SMA) have been investigated on the Abrasive Water Jet (AWJ) machine. After the cutting process, kerf width of the samples were investigated. The experimental results showed that water pressure, traverse speed and abrasive flow rate have a great effect on kerf width and dimension tolerance.

International Iron & Steel Symposium
UDCS

Ali GÜNEN Mehmet DEMİR Erdogan KANCA Mustafa Serdar KARAKAŞ Murat YILDIZ Ersan KIRAR M. Mustafa ERŞEN

Rolling has an important place in iron and steel industry due to the advantages such as production speed, continuity and easy to process applications. Roll materials must be resistant to high heat temperature conditions, high breaking resistance, good surface quality, proper hardness, good wear resistance and thermal shocks. However, producing an alloy material with all of these features together will be very costly. Instead of producing a roll material having all of these properties, it is more economical and practical approach to provide these characteristics by surface modification. In this study, External cooling rollers (ECR) coated by different four techniques which, Flame spray, boriding, titanizing and borotitanizing. After the coating process, the thickness of the coating layer, hardness, and layer structures examined by optic microscope, scanning electron microscope, micro hardness, and X-ray analyses. A wide range of coating thicknesses and microhardness values obtained depending on coating technique. The highest mircohardness obtained in the titanized sample, but the lowest coating thickness. The obtained hardness values were 3 times higher than those in the current application. The cost of rolling will be reduced by increase in ECR tool life.

International Iron & Steel Symposium
UDCS

Mehmet DEMİR Ali GÜNEN Mustafa Serdar KARAKAŞ Vahdettin Koç Mustafa Sabri Gök Ahmet ÇÜRÜK

Titanium (Ti) + Niobium (Ni) doped Interstitial Free (IF) steel grades (Ti + Nb IF steel) are widely used in steel industries because of their good formability properties. In this study, the effect of cold rolling reduction rate on the microstructure and mechanical properties of IF steel was investigated in details. The samples subjected to cold rolling with various reduction rates ranging from 40% to 80% at constant annealed temperature. The changes in microstructure were examined with optical microscope. Mechanical properties such as cupping values, anisotropy values (r) yield strength, tensile strength and elongation. were examined by Erichson and tensile test. The results affects the microstructural evolution and carbide precipitations significantly, in turn altering the mechanical properties. Increasing amount of cold rolling reduction rate resulted for an increase in the cupping values, anisotropy values, yield strength and elongation, whereas it leaded to a decrease in tensile strength. As a result of this trial experiment it can be said that reduction rate has a great effect on mechanical and microstructure properties of Ti+Nb doped IF steel. clearly demonstrated that the reduction rate of cold rolling.

International Iron & Steel Symposium
UDCS

Ali GÜNEN M. Mustafa ERŞEN Erdogan KANCA Murat YILDIZ Mehmet DEMİR Bülent KURT Mustafa Sabri Gök