Pack Carburizing Baja Karbon Rendah

Abstract

Abstrak:

Penelitian ini bertujuan untuk mengetahui sifat mekanis khususnya kekerasan dan kekuatan tarik baja karbon rendah setelah dikarburasi menggunakan media karburasi (carburizer) campuran 80% arang bambu dan 20% BaCO3 sebagai energizer. Penelitian dilakukan dengan memasukkan specimen uji ke dalam kotak pack carburizing yang telah berisi media karburasi, kemudian kotak pack carburizing dimasukkan ke dalam dapur pemanas dan dipanaskan sampai suhu 9500C. Pada suhu tersebut specimen ditahan selama 4 jam kemudian kotak baja dikeluarkan dari dapur pemanas. Specimen dikeluarkan dari kotak baja dan didinginkan di udara. Selanjutnya dilakukan pengujian kekerasan menggunakan Vikers Testing Machine. Sedangkan uji tarik dilakukan dengan menggunakan Universal Testing Machine. Hasil penelitian menunjukkan bahwa setelah dikarburizing baja karbon rendah mengalami perubahan sifat mekanis. Kekerasan raw material sebesar 183,60 HV1 meningkat 100,68 % menjadi 368,46 HV1 setelah dikarburizing. Demikian juga kekuatan luluh dan kekuatan tarik yang semula 31,99 kg/mm2 dan 42,08 HV1 kg/mm2 meningkat secara berturut turut menjadi 48,94 kg/mm2 dan 55,05 kg/mm2. Namun di sisi lain, terjadi penurunan elongasi yang semula 30,07 % menurun menjadi 7,6%. Kata kunci: Pack carburizing, kekerasan, kekuatan tarik, media karburasi

Abstract:

This research is focused on the mechanical properties, especially on the hardness and tensile strength of low carbon steel after pack carburizing process by use of carburizer consisting of 80% bamboo coal and 20% BaCO3 as energizer. The research was carried out by packing of low carbon steel specimens in a steel box filled of carburizer. The steel box was then loaded into electric furnace, heated up to 9500C, and socked at the temperature during 4 hours. After that socking time, the steel box was drooped out from electric furnace and specimens were taken from steel box and colded in the air. Furthermore, it was undertaken hardness and tensile test by use of Vickers Hardness Tester and Universal Testing machine respectively. The result of research showed that there were mechanical properties changes of low carbon steel after carburizing process. Hardness of raw material (183.60 HV1) increased about 100.68% to 368.46 HV1 after carburizing. Furthermore, yield strength of 31.99 kg/mm2 and tensile strength of 42.08 kg/mm2 also increased to 48.94 kg/mm2 and 55.05 kg/mm2 respectively. However, there was a decrease in elongation from 30.07% to 7.6%. Keywords: Pack carburizing, hardness, tensile strength, carburizer