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ABSTRAKPada proses pembentukan logam metode die casting, nitridisasi memegang
peranan penting dalam peningkatan umur pakai dies. Inovasi proses perlakuan
permukaan yang dilakukan sebelum nitridisasi bertujuan untuk meningkatkan efisiensi nitridisasi dan kedalaman lapisan nitrida pada baja H13 Modifikasi.
Nitridisasi gas dilakukan dalam vacuum furnace, pada suhu 510oC selama 5 jam.Shot peening dilakukan dengan menggunakan bola baja dengan tekanan 461 kPa.
Shot blasting dilakukan sebagai metode pembersihan permukaan material menggunakan partikel SiC. Karakterisasi permukaan sampel sebelum dan sesudah
variasi proses difokuskan pada perubahan struktur mikro, distribusi kekerasan
mikro, dan komposisi kimia lapisan nitridisasi. Dari proses nitridisasi yang
didahului shot peening, didapatkan kekerasan maksimal 1196 HV dengan kedalaman efektif lapisan difusi 72 !m. Nilai ini lebih besar dari proses nitridisasi
tanpa didahului perlakuan permukaan, yang menghasilkan kekerasan maksimal 1101,4 HV dengan kedalaman efektif lapisan difusi 54!!m. Variasi proses nitridisasi dengan shot peening menghasilkan ketebalan white layer 4,1!!m; lebih tebal dari proses nitridisasi tanpa shot peening 3,7!!m. Sedangkan pada nitridisasi
yang tidak didahului perlakuan permukaan tidak ditemukan adanya white layer.
ABSTRAKIn the die casting practice, nitriding represents an important factor in enhancing
the service life of dies. Surface treatment innovation prior to nitriding in this
research aim to increased the nitriding efficiency and the depth of nitrided layer of
H13 Modification steel. The gas nitriding process was performed at temperature
510oC for 5 hours in a vacuum furnace. Shot peening was performed prior to
nitriding using a cast steel ball with 461 kPa nozzle pressure. Shot blasting with
SiC particle was also performed as a surface cleaning method. Characterizations
on the surface of steel were done before and after the variation of nitriding process
with focused on the microstructure, microhardness profile, and the chemical
composition of the nitrided layer formed. It was found that shot peening prior to
nitriding significantly increased the nitriding kinetics, that results in 1196 HV
maximum surface hardness with 72 !m effective case depth. This results were
higher than the nitriding process without prior surface preparation, which have
only 1101,4 HV maximum surface hardness with 54!!m effective case depth.
While the nitrided only process did not formed a white layer, the shot peened
sample was found to have a white layer with 3,7!!m thick., In the die casting practice, nitriding represents an important factor in enhancing
the service life of dies. Surface treatment innovation prior to nitriding in this
research aim to increased the nitriding efficiency and the depth of nitrided layer of
H13 Modification steel. The gas nitriding process was performed at temperature
510oC for 5 hours in a vacuum furnace. Shot peening was performed prior to
nitriding using a cast steel ball with 461 kPa nozzle pressure. Shot blasting with
SiC particle was also performed as a surface cleaning method. Characterizations
on the surface of steel were done before and after the variation of nitriding process
with focused on the microstructure, microhardness profile, and the chemical
composition of the nitrided layer formed. It was found that shot peening prior to
nitriding significantly increased the nitriding kinetics, that results in 1196 HV
maximum surface hardness with 72 !m effective case depth. This results were
higher than the nitriding process without prior surface preparation, which have
only 1101,4 HV maximum surface hardness with 54!!m effective case depth.
While the nitrided only process did not formed a white layer, the shot peened
sample was found to have a white layer with 3,7!!m thick.]
S54223-Rizkhi Aldilla.pdf :: Unduh