PENGARUH PERLAKUAN PENDINGINAN PASCA PENGELASAN PADA STAINLESS STEEL SA 240 TYPE 304 DAN STAINLESS STEEL SA 240 TYPE 316 MENGGUNAKAN PROSES SMAW TERHADAP KETAHANAN PITTING CORROSION

Ferdianzah, Gandhi (2015) PENGARUH PERLAKUAN PENDINGINAN PASCA PENGELASAN PADA STAINLESS STEEL SA 240 TYPE 304 DAN STAINLESS STEEL SA 240 TYPE 316 MENGGUNAKAN PROSES SMAW TERHADAP KETAHANAN PITTING CORROSION. Diploma thesis, POLITEKNIK PERKAPALAN NEGERI SURABAYA.

Full text not available from this repository.

Abstract

ABSTRAK Di berbagai bidang industri banyak digunakan austenitic stainless steel tipe 304 untuk memberikan ketahanan korosi. Namun fakta di lapangan tipe 304 masih rentan terkena korosi salah satunya yaitu pitting corrosion. Untuk memberikan ketahanan pitting digunakan austenitic stainless steel tipe 316 yang terdapat unsur peningkat ketahanan pitting yaitu molibdenum. Adanya fenomena sensitisasi saat pendinginan pasca pengelasan kedua tipe tersebut dapat menimbulkan endapan karbida (Cr23C6 ) yang mengakibatkan terbentuknya zona miskin chromium sebagai subyek pitting. Hal ini berakibat ketahanan pitting pada sambungan las akan menurun, untuk mengurangi sensitisasi agar zona miskin chromium berkurang perlu dilakukan perlakuan pendinginan pasca pengelasan. Pada penelitian ini terdapat 2 variabel perlakuan pendinginan pasca pengelasan meliputi pendinginan udara normal dan pendinginan udara paksa menggunakan compressor. Selanjutnya dilakukan pengujian pitting corrosion berdasarkan standard ASTM G48 dan evaluasi pitting berdasarkan ASTM G46 meliputi densitas, ukuran, kedalaman, dan bentuk pitting. Berdasarkan hasil penelitian, untuk stainless steel tipe 304 maupun tipe 316 dengan perlakuan pendinginan udara paksa memberikan ketahanan pitting yang lebih baik daripada perlakuan pendinginan udara normal. Sama halnya dengan hasil evaluasi pitting, pada kedua tipe stainless steel untuk densitas, ukuran, kedalaman, dan bentuk terdapat perbedaan nilai tetapi masih dalam rating yang sama. Kata kunci : austenitic stainless steel, sensitisasi, endapan karbida, zona miskin chromium, pitting corrosion ABSTRACT In various industrial, widely used of type 304 austenitic stainless steel to provide corrosion resistance. But the facts on aplication of type 304 still susceptible to corrosion one of pitting corrosion. For provide pitting resistance, used austenitic stainless steel type 316 which contained molybdenum as enhancing the pitting resistance. The phenomenon of sensitization on both types of welding resulted carbide precipitates which effect formation of chromium depleted zones that are subject of pitting. It can decreases pitting resistance of weld, to minimize the sensitization that reduced chromium depleted zones necessary cooling treatment after welding. In this study, there are two variable cooling treatment after welding includes normal air cooling and forced air cooling using a compressor. Furthermore pitting corrosion testing by standard ASTM G48 and evaluation of pitting by ASTM G46 include density, size, depth and shape of pitting. Based on the results, for stainless steel type 304 and type 316 with forced air cooling treatments provide better pitting resistance than normal air cooling treatment. Similiar to the results of the evaluation of pitting, in both types of stainless steel for density, size, depth, and shape, there are differences in value but still within the same rating. Keyword : austenitic stainless steel, sensitization, carbide precipitates,chromium depleted zones, pitting corrosion

Item Type: Thesis (Diploma)
Subjects: T Technology > T Technology (General)
Divisions: Jurusan Teknik Bangunan Kapal > Teknik Pengelasan
Depositing User: Unnamed user with email repository@ppns.ac.id
Date Deposited: 07 Sep 2018 05:22
Last Modified: 07 Sep 2018 05:22
URI: http://repository.ppns.ac.id/id/eprint/376

Actions (login required)

View Item View Item