Pengaruh Penambahan Aluminium dan Waktu Aging pada Proses Precipitation Hardening terhadap Struktur Mikro dan Sifat Kekerasan Paduan Tembaga-Seng (Cu-37%Wt Zn)

Ismail, Muhammad Fajar (2017) Pengaruh Penambahan Aluminium dan Waktu Aging pada Proses Precipitation Hardening terhadap Struktur Mikro dan Sifat Kekerasan Paduan Tembaga-Seng (Cu-37%Wt Zn). Undergraduate thesis, Institut Teknologi Sepuluh Nopember.

[img]
Preview
Text
2713100100-Undergraduated_Theses.pdf - Published Version

Download (18MB) | Preview

Abstract

Kuningan (Cu-Zn) meupakan paduan antara tembaga dan seng yang banyak digunankan dalam bidang industri untuk propeller, kabel serta mur dan baut. Kuningan memiliki sifat yang unggul seperti ketahanan korosi, konduktivitas listrik, konduktivitas panas serta formability dan machinability yang baik, namun memiliki kekerasan yang kurang tinggi. Penambahan paduan dan perlakuan panas dilakukan untuk meningkatkan sifat kekerasan kuningan. Tujuan dari diadakannya penelitian ini adalah untuk menganalisis pengaruh penambahan aluminium dan waktu aging terhadap struktur mikro dan sifat kekerasan paduan Cu-37Zn. Paduan Cu-37Zn dan Cu-36Zn-1Al dilebur menggunakan furnace dengan temperatur 1100°C. Setelah dilebur logam cair dituang pada cetakan pasir dan didinginkan. Selanjutnya dilakukan pengujian komposisi kimia. Kemudian dilakukan proses precipitation hardening yang terdiri dari proses solution treatment dan aging. Proses solution treatment dilakukan pada temperatur 450ºC dilanjutkan pendinginan cepat dengan media air. Kemudian dilakukan proses aging pada temperatur 250ºC dengan waktu aging 1,2,3 dan 4 jam. Pengujian yang digunakan dalam penelitian ini adalah pengujian komposisi kimia dengan Optical Emission Spectroscopy (OES), difraksi sinar-X (XRD), metalografi dan pengujian sifat kekerasan. Struktur mikro yang terbentuk adalah fasa α dan β. Penambahan aluminium merubah bentuk strukturmikro dari dendritik menjadi equiaksial dan mempromosikan lebih banyak fasa β sehingga meningkatkan kekerasan paduan Cu-37Zn. Struktur mikro dari paduan Cu-37Zn dan Cu-36Zn-1Al yang dihasilkan setelah solution treatment tidak mengalami perubahan fasa, akan tetapi menurunkan luas area dari fasa β. Setelah proses aging, luas area fasa β menjadi lebih besar seiring dengan meningkatnya waktu aging. Proses precipitation hardening meningkatkan kekerasan paduan Cu-37Zn dan Cu-36Zn-1Al. Nilai kekerasan paduan Cu-37Zn dan Cu-36Zn-1Al tertinggi pada paduan precipitation hardening dengan waktu aging 3 jam dengan nilai 73,8 HV dan 147,7 HV. ================================================================================================ Brass (Cu-Zn) is an alloy of copper and zinc that used in many industrial fields, such as propeller, pipes, nuts and bolts. It has good corrosion resistance, electrical conductivity, thermal conductivity also good formability and machinability but has a low hardness. Adding an alloy and heat treatment process needed to increase hardness properties. In this study, the addition of aluminum (Al) of 1% al followed by precipitation hardening to determine their effects on the microstructure and properties of hardness in the alloy Cu-37Zn. This alloy is melted using a furnace with temperatur 1100°C without holding. After melted, molten metal is poured in sand molds and cooled. Next, chemical composition was tested. Then precipitation hardening process which consist solution treatment and aging was occured. Solution treatment process was carried out at a temperature of 450°C continued for rapid cooling with water cooling and aging process is carried out at temperature 250°C with aging time 1,2,3 and 4 hours. After aging process, alloys was cooled in air cooling. The test used in this research is chemical composition test with optical emission spectroscopy (OES), x-ray diffraction (XRD), metallography and hardness test. Microstructure that’s formed is α and β phase. The addition of aluminum changed the shape of the microstructure from dendritic to equiaxed and promoting more β phase that increased the hardness of Cu-37Zn alloys. The microstructure of Cu-37Zn and Cu-36Zn-1Al alloys produced after solution treatment did not undergo phase change, but decreased the area of β-phase. After the aging process, the area of β-phase becomes larger as the aging time increases. The precipitation hardening process increases the hardness of Cu-37Zn and Cu-36Zn-1Al alloys. The highest hardness of Cu-37Zn and Cu-36Zn-1Al alloys is precipitation hardening alloys for 3-hour aging time with 73.8 and 147.7 HV

Item Type: Thesis (Undergraduate)
Uncontrolled Keywords: Cu-Zn, Cu-Zn-Al, Precipitation Hardening, Waktu Aging
Subjects: T Technology > TN Mining engineering. Metallurgy
T Technology > TS Manufactures
Divisions: Faculty of Industrial Technology > Material & Metallurgical Engineering > (S1) Undergraduate Theses
Depositing User: Muhammad Fajar Ismail
Date Deposited: 10 Nov 2017 06:34
Last Modified: 05 Mar 2019 06:23
URI: http://repository.its.ac.id/id/eprint/42568

Actions (login required)

View Item View Item