Sains Malaysiana 42(12)(2013): 1743–1750

 

Optimization of Injection Molding and Solvent Debinding Parameters of

Stainless Steel Powder (SS316L) Based Feedstock for Metal Injection Molding

(Pengoptimuman Pengacuan Suntikan dan Penyahikatan Larutan bagi Bahan Suapan Berasaskan

Serbuk Keluli Tahan Karat (SS316L) untuk Pengacuanan Suntikan Logam)

 

MUHAMMAD ILMAN HAKIMI CHUA, ABU BAKAR SULONG*, MOHD FAZURI ABDULLAH & NORHAMIDI MUHAMAD

Department of Mechanical and Material Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

 

Received: 3 April 2012/Accepted: 22 May 2012

 

ABSTRACT

In this study, injection molding parameters, including green strength, surface quality and green part density, were optimized using the L18 Taguchi orthogonal array. The L25 Taguchi method was used to optimize the green density of solvent debinding parameters. The feedstock consisted of stainless steel powder (SS316L), with powder loading fractions of 63, 63.5 and 64 v/o. The binder compositions used in the study were polyethelene glycol (PEG-73 wt. %), polymethyl methacrilate (PMMA-25 wt. %), and stearic acid (2 wt. %). The Taguchi method was used to optimize the injection parameters. The obtained optimum parameters were as follows: mold temperature of 65^oC, injection temperature of 145^oC, injection pressure of 650 bar, injection flow rate of 20 m3/s, holding time of 5 s and powder loading of 64% v/o. Analysis of variance results showed that mold temperature has the greatest influence in the production of good green part surface quality and that powder loading gave the best green part strength. Immersion time and temperature were used to optimize for solvent debinding parameters. By optimizing the solvent debinding parameters, an immersion temperature of 61^oC and immersion time of 5 h produced the highest density which is the optimum value gain in this study.

 

Keywords: Debinding; density; green compact strength; injection parameters; metal injection molding; Taguchi method

 

ABSTRAK

Dalam kajian ini, parameter pengacuanan suntikan logam bagi kekuatan jasad hijau, kualiti permukaan dan ketumpatan jasad hijau dioptimumkan menggunakan Kaedah Ortogon Taguchi L18. Taguchi L25 pula digunakan bagi mengoptimumkan parameter penyahikatan larutan bagi ketumpatan jasad hijau. Bahan suapan yang digunakan terdiri daripada serbuk keluli tahan karat (SS316L) dengan pecahan pembebanan serbuk sebanyak 63, 63.5 dan 64 v/o. Bahan pengikat yang digunakan pula terdiri daripada polietelina glikol (PEG-73 wt. %), polimetil metaklirat (PMMA-2 5wt. %) dan asik stearik (2 wt. %). Kaedah Taguchi digunakan bagi mendapatkan nilai optimum dalam kajian ini. Parameter optimum bagi penyuntikan yang diperoleh adalah seperti berikut: Suhu acuan pada 65^oC, suhu penyuntikan pada 145^oC, tekanan penyuntikan pada 650 bar, kadar alir pada 20 m3/s, masa padatan pada 5 s dan pembebanan serbuk pada 64 v/o. Berdasarkan analisis ANOVA, suhu acuan memberikan pengaruh yang paling tinggi bagi mendapatkan jasad hijau yang mempunyai ketumpatan yang tinggi serta kualiti permukaan yang baik manakala pembebanan serbuk memberikan kekuatan jasad akhir yang terbaik. Pengoptimuman bagi penyahikatan menunjukkan suhu rendaman pada 61^oC dan masa rendaman selama 5 jam memberikan ketumpatan jasad yang tertinggi dalam kajian ini.

 

Kata kunci: Kaedah Taguchi; kekuatan jasad hijau; ketumpatan;; parameter penyuntikan; pengacuan suntikan logam; penyahikatan

 

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*Corresponding author; email: abubakar@eng.ukm.my