PENGARUH QUENCHING DENGAN MEDIA AIR TERHADAP KEKERASAN DAN STRUKTUR MAKRO MATERIAL BAJA KARBON RENDAH HASIL HARDFACING

Pada penelitian ini bertujuan untuk mengetahui pengaruh directquenchingdan furnace quenching dengan media air terhadap nilai kekerasandan struktur makrohasil hardfacingdualapis menggunakanelektroda HV 600. Untuk pembuatan spesimen terbagi menjadi 6 spesimen yang terdiri dari direct quenchingsatu, direct quenchingdua, non treatment, holding time10 menit, 20 menit, dan 30 menit. Pada proses directquenchingsatu dilakukan hardfacingdua lapis dengansatu kali pendinginan, pada proses directquenchingdua dilakukanhardfacingdua lapis dengandua kali pendinginan. Selanjutnya pada spesimen furnace quenchingdilakukanproses hardfacing,dilanjutkan proses heattreatmentdengan variasi holdingtimeserta dilakukan quenchingmenggunakan air yang bersuhu 28°C.padahasil uji keras spesimen directquenchingmempengaruhi nilai kekerasan, yang dimana nilai kekerasan tertinggi terdapat di spesimen directquenching635,33HVN, dan nilai kekerasan terendah terdapat pada spesimen direct quenchingsatu 581,93 HVN. Pada spesimen furnace quenchingsemakin lama holding timepada saat heat treatmentmaka kekerasannya menurun, dimana pada spesimen holdingtime10 menit dengan nilai kekerasan 716,3 VHN, dan nilai terendah terdapat pada spesimen holding time30 menit dengan nilai kekerasan 559,77 HVN. Pada struktur makro tidak terjadi perbedaan signifikan antara spesimen direct quenchingdan furnace quenching. aims to study the effect of direct cooling and furnace cooling with air media on the hardness and macro structure results of two-layer hardfacing using HV 600 electrodes. For the manufacture of specimens divided into 6 specimens consisting of direct cooling, direct cooling, without treatment, time incarceration of 10 minutes, 20 minutes and 30 minutes. In the direct quenching process one is done with two layers of hardfacing with one time finishing, in the direct quenching process two is done with two layers of hardfacing with two convincing. Furthermore, hardfacing is carried out in the furnace quenching specimen, followed by heat treatment with holding time variations and quenching using water at 28 ° C. the lowest defense value is required in the direct cooling specimen of 581.93 HVN. In the furnace of the holding specimen for long time during heat treatment, the increase decreases, the specimen holds 10 minutes with a hardness value of 716.3 VHN, and the lowest value required for the specimen holds 30 minutes with a value of 559.77 HVN. In the macro structure there is no significant difference between the specimens of direct quenching and furnace quenching. Keywords: Quenching, hardfacing, Hardness, Macro Structure, Low Carbon Steel