Analisa Pengaruh Media Pendingin Air dan Air Garam Terhadap Sifat Mekanis Sambungan Lap Joint Menggunakan Las SMAW Baja Karbon Rendah

Abstrak

At present welding techniques have been used or developed widely in the connection of building construction and machine construction, so it can be said that in the world of welding there is almost no metal that cannot be connected with welding techniques. However, each welding process has different characteristics of defect types. Rapid cooling with water tends to increase the hardness of the HAZ weld compared to slow cooling (air / oil). The purpose of the study is to determine how the effect of water and salt water cooling media on the mechanical properties of lap joint connections using low carbon steel SMAW on tensile and impact load testing, In this study using ST37 carbon steel with a sample size of 15x10x5 cm which was then welded with a lap joint model using SMAW welding. The results of the study obtained the highest average tensile stress value shown by specimens with ordinary water cooling media of 463.567 MPa, and the lowest tensile stress value shown by air cooling media of 438.233 MPa. Then the highest average impact energy value was shown by the air-cooled media at 90.190 Joules, and the lowest impact energy value was shown by the ordinary water- cooled media at 76.833 Joules. So it can be concluded that ordinary water-cooled media can increase tensile strength due to rapid cooling and air-cooled media can increase impact strength. Keywords: carbon steel, welding, lap joint, tensile test, impact test

Kata kunci

• Impact
• Lap joint
• Steel
• Tensile
• Welding