Yohanes Yohanes
Mechanical Engineering Department, Faculty of Engineering, Universitas Riau, Indonesia

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Effect of Rotational Speed on Hardness Value and Area of Vertical Bar-Plate Rotary Friction Weld Joint Yohanes Yohanes; Meipen Meipen
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 66 No 3 (2022): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v66i3.327

Abstract

This study aims to determine the effect of rotational speed on the weld joint area and the hardness value of vertical bar-plate friction welding on dissimilar materials. Several testing methods were carried out, namely liquid penetrant, macro-observations, micro-observations and hardness test to investigation the welding results. The results of the liquid penetrant test have no effect on the welding specimens. Based on macro-observations was revealed a large enough cavity at a speed of 2.484 rpm with a cavity length of 4.76 mm, then getting smaller at a speed of 2.613 rpm with a cavity length of 2.63 mm. Then, at a speed of 4.335 rpm, no cavities were found. The micro-observation was a change in the microstructure, where in the weld metal area produces fine grains that affect the hardness value. The hardness value increases as it approaches the weld area. The highest hardness value at a speed of 4.335 rpm with a hardness value of 148.10 VHN, while the lowest hardness at a rotational speed of 2.484 rpm has a hardness value of 140.44 VHN.
Analysis of Current and Electrode Types on Welding Defects in ASTM A36 Mild Steel Herisiswanto Herisiswanto; Yohanes Yohanes; Khoirul Hafisuddin
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 66 No 3 (2022): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v66i3.303

Abstract

The purpose of this study is to analyze the welding defects that occurring in the SMAW (Shielded Metal Arc Welding) process. This study used experimental method to investigate the various types of electrodes and welding current. The welding process in this study used ASTM A36 low carbon steel with specimen dimensions of 8 mm thick, 80 mm wide, and 100 mm long. The welding process was carried out in an underhand position (1G) using a V-seam layer with a SMAW welding machine, which a sliding adaptive two axis system with speed control. The types of electrodes used were E6013 and E7018 electrodes with a diameter of 3.2 mm. The current variations used 90 A, 105 A and 120 A. The test methods used the Penetrant Test, Visual Test (Non Destructive Test) and Tensile Test (Destructive Test). The results of this study were: 1) the welding defects that often occurring at the E6013 electrode due to undercut and at the E7018 electrode caused by the porosity, 2) at a current of 120 A the occurrence of welding defects was minimal, and 3) the tensile strength of E7018 was greater than E6013.
Effect of Spindle Speed of Bar-Plate Rotary Friction Welding Machine on Joint Interface Area and Hardness Value Michael Simorangkir; Yohanes Yohanes; Muftil Badri
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 67 No 1 (2023): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v67i1.322

Abstract

This study aims to determine the effect of the rotational speed parameter on the joint interface weld area and the value of hardness on similar materials. Welding parameters used the rotational speed of 2,484 rpm, 2,613 rpm and 4,335 rpm. Test method used in this research was liquid penetrant, macro and micro-observation and hardness test. The results of the liquid penetrant test showed no defects on the surface of the connection. In macro-observation, where there is a fairly large void at rotational speed of 2,484 rpm, which has length is 2,69 mm, then shrinks at 2,613 rpm to 1,52 mm, then at 4,335 rpm there is no visible void. In micro-observations showed that the weld metal area had a finer grain structure than the HAZ (Heat Affected Zone) and base metal areas this affect hardness value. The results of the hardness test are that the higher the rotational speed the higher the hardness value produced.