Examination of microstructure and mechanical properties of different steel with by arc welding methods

In this study, submerged arc welding and electric arc welding with basic electrode techniques of X70 and St 52 steel matherials had been combined. Chemical analysis of X70 and St 52 steel materials that has been used in experimental studies, had been detected with ARL 3460 spectrometric analysis device. To detected hardness values of the samples, hardness tests had been applied to 15 different with sections. The peak point of the results was measured on X70 steel which has been welded by basic elektrode techniques as 310 HV0,2. For detecting of maximum tensile strenght and % elangation tension test and bend tests had been applied to the samples. Test samples had been prepared by DIN 50125 standarts. The maximum value of tensile strenght had been measured 665 Mpa at X70 steel which was welded by basic electrode technique. Maximum bending strenght was measured 761 Mpa at X70 steel matherial which had been welded by submerged arc welding techique. Maximum elangation value olso measured % 15,99 at X70 steel which was welded by basic electrode techique. The purpose of Taguchi modelling is performing minimum tests and experimenting the effects of test parametres on final results via making up an orthogonal series. Taguchi method had been used for detecting the effect of amper and weld speed on hardness results on X70 and St 52 matherials, which had been welded by submerged arc welding. Depending literature hardness is increasing higher weld speed and low ampers. Prorided Taguchi method results had been showed that X70 matherial hardness is higher comparing St 52 matherial. In this study, obtained rresults are statically mainingful depending on calculated 'p' value is 0,0042<0,05. Welding speed (% 50,4) calculated the most effective parameter on hardness by varient analyses. Another effective parameter is matherial selection (% 40,2), and the less effective parameter was amper (%5,3). Finally depending on varient analyses table failure rate % 4,1 and that means that the results are reliable by % 95,9.