Injection Moulding of A Bimodal Size Distribution 316L Stainless Steel Powders

2012 ◽  
Author(s):  
M.A. Omar
Keyword(s):  
Stainless Steel ◽  
Polyethylene Glycol ◽  
Polymethyl Methacrylate ◽  
Injection Moulding ◽  
Raw Materials ◽  
Fine Powder ◽  
Steel Powder ◽  
Water Leaching ◽  
Coarse Powder ◽  
Metal Injection Moulding

Bagi mengurangkan kos bahan mentah untuk proses pangacuan suntikan logam (MIM), bahan teracu yang diperbuat daripada serbuk logam keluli tahan karat dengan nisbah serbuk logam kasar dan halus yang berlainan telah diselidiki. Bahan suapan tersebut disediakan dengan menggunakan sistem bahan pengikat komposit yang terdiri sebahagian besarnya polietilina glikol (PEG) yang berlainan berat molekulnya dan emulsi polimetil metakrilat (PMMA) yang seterusnya disuntik ke dalam bentuk segiempat tepat dengan suhu muncung suntikan logam pada 140°C. Hasil ujikaji menunjukkan kekuatan bahan teracu meningkat secara linear dengan peningkatan nisbah serbuk halus di dalam campuran dan optimum pada 30 wt.% dan seterusnya berlaku penurunan dengan peningkatan nisbah serbuk halus. Peningkatan serbuk logam halus di dalam campuran juga dapat meningkatkan ketumpatan akhir dan kekerasan bahan tersinter. Kadar penyingkiran polietilina glikol semasa proses pengurasan air meningkat dengan penurunan nisbah serbuk logam halus yang mana menunjukkan bahawa serbuk logam kasar memberi kesan ketara ke atas proses penyingkiran bahan pengikat. Kata kunci: pengacuan suntikan logam; polietilina glikol; polimetil metakrilat; pengurusan air; pengsinteran In an effort to lower the cost of raw materials of metal injection moulding (MIM), a moulded part made of a different ratio of coarse and fine stainless steel powder mixtures, ranging from 10 to 50 wt.% of fine powder were investigated. The feedstocks were prepared using a composite binder system which consist of a major fraction of polyethylene glycol (PEG) with different molecular weight and a minor fraction of polymethyl methacrylate (PMMA) emulsion and subsequently moulded into a rectangular shape at the nozzle temperature of 140°C. The results show that the green strength of the moulded part increased linearly with the increased of the ratio of fine powder to an optimum of 30 wt.% and decreased slightly with the increased of coarse/fine ratio. An increase in the fine powder in the mixture, improved the final densification and hardness of the sintered parts. The rate of PEGs removed during water leaching substantially increased with the lower ratio of fine powder, which suggest that the coarse powder has significant influence on the removal of the binder. Key words: metal injection moulding; polyethylene glycol; polymethyl methacrylate; water leaching; sintering

Pemilihan Bahan Suapan bagi Proses Pengacuan Suntikan Logam Berdasarkan kepada Kajian Sifat Reologi

2012 ◽  
Author(s):  
Norhamidi Muhamad ◽  
Khairur Rijal Jamaludin ◽  
Sri Yulis M. Amin ◽  
Mohd Nizam Ab. Rahman
Keyword(s):  
Stainless Steel ◽  
Injection Molding ◽  
Rheological Properties ◽  
Polymethyl Methacrylate ◽  
Fine Powder ◽  
Flow Behaviour ◽  
Metal Injection Molding ◽  
Coarse Powder ◽  
Flow Behaviour Index ◽  
Behaviour Index

Sifat reologi bahan suapan acuan suntikan logam MIM yang disediakan dengan keluli tahan karat 316L pengabusan gas dan, polymethyl methacrylate (PMMA), polietelena glikol (PEG) dan asid sterik sebagai bahan pengikat telah dikaji. Dai kapilari L/D = 10 telah digunakan dalam kajian ini. Serbuk keluli tahan karat kasar dan halus telah diadunkan dengan bahan pengikat pada beban serbuk 64% dan 65% isipadu. Kesemua bahan suapan mempamerkan tingkahlaku pseudo plastik memandangkan indek tingkahlaku alirannya kurang daripada 1, tetapi indek tersebut berkadar songsang terhadap beban serbuk. Seterusnya, indek tingkahlaku bagi serbuk kasar didapati lebih besar berbanding serbuk halus. Bahan suapan 16_64 lebih peka berbanding bahan suapan yang lain, dan bahan suapan 31_65 pula didapati kurang peka terhadap suhu dan tekanan. Bagaimanapun, kepekaan juga didapati berkadar songsang terhadap beban serbuk. Maka, indek kebolehacuan bagi 31_64 adalah yang terbaik, dan hasil kajian mendapati bahawa beban serbuk 64% isipadu menghasilkan kebolehacuan bahan suapan yang lebih baik. Akhirnya, kajian ini menyimpulkan bahawa kesemua bahan suapan sesuai untuk disuntik ke dalam acuan kerana sifat reologinya menunjukkan penipisan ricih apabila tegasan ricih dikenakan terhadapnya. Bagaimanapun, bahan suapan pada beban serbuk 64% isipadu adalah yang lebih sesuai disebabkan oleh indek kebolehacuan yang lebih tinggi daripada 65% isipadu. Kata kunci: Pengacuan suntikan logam, reologi, indek tingkahlaku aliran, tenaga pengaktifan, indek kebolehacuan Rheological properties of the metal injection molding (MIM) feedstock prepared with gas atomized 316L stainless steel and, polymethyl methacrylate (PMMA), polyethylene glycol (PEG) and stearic acid as binder have been investigated. Capillary rheometer with die of L/D = 10 was used in the investigation. Coarse and fine stainless steel powders were mixed with binders at powder loading of 64% and 65% volume. All feedstocks exhibit pseudo plastics behaviour as the flow behaviour indexes were less than one, but it is inversely proportional to the powder loading. Moreover, the flow behaviour index of the coarse powder is larger than the fine powder particles. Feedstock 16_64 exhibits higher sensitivity among other feedstocks while 31_65 was least sensitive to the temperature and pressure. However, the sensitivity was also inversely proportional to the powder loading. Thus, moldability index of the 31_64 is the best and result shows that powder loading 64% volume gives better moldability to the feedstocks. Finally, the investigation concluded that the feedstocks are suitable to be injection molded because the rheological properties demonstrate a shear thinning when subjected to shear stress. However, feedstock with the powder loading of 64% volume is the most suitable as the moldability index is higher than the 65% volume feedstocks. Key words: Metal injection molding, rheology, flow behaviour index, activation energy, moldability index

Effects of Powder Characteristics on Selective Laser Melting of 316L Stainless Steel Powder

2011 ◽  
Vol 189-193 ◽  
pp. 3664-3667 ◽  
Author(s):  
Sheng Zhang ◽  
Qing Song Wei ◽  
Guang Ke Lin ◽  
Xiao Zhao ◽  
Yu Sheng Shi
Keyword(s):  
Stainless Steel ◽  
Selective Laser Melting ◽  
316L Stainless Steel ◽  
Fine Powder ◽  
Steel Powder ◽  
Laser Melting ◽  
Broad Size Distribution ◽  
Lower Oxygen ◽  
Powder Characteristics ◽  
Loose Powder

316L stainless steel parts were manufactured via selective laser melting . This work stu- dies the effects of powder characteristics such as particle size and particle shape composition on the density. It shows that the powder with a broad size distribution and using spherical fine powder can lead to an increase in the density of the loose powder and thus the densification of the laser melted powder. The aerosol powder forms parts of lower oxygen content well, and the density can reach to 90%.

Sintering temperature effects on the properties of stainless steel 316L compact fabricated by metal injection moulding

2019 ◽  
Vol 33 (1/2) ◽  
pp. 37 ◽  
Author(s):  
Nur Syawanie Manam ◽  
Wan Sharuzi Wan Harun ◽  
Mohd Halim Irwan Ibrahim ◽  
Nur Zalikha Khalil ◽  
Mahendran Samykano
Keyword(s):  
Stainless Steel ◽  
Injection Moulding ◽  
Temperature Effects ◽  
Sintering Temperature ◽  
Stainless Steel 316L ◽  
Metal Injection Moulding

Fabrication of stainless steel based composite by metal injection moulding

2018 ◽  
Vol 5 (2) ◽  
pp. 6805-6814 ◽  
Author(s):  
C Veeresh Nayak ◽  
MR Ramesh ◽  
Vijay Desai ◽  
Sudip Kumar Samanta
Keyword(s):  
Stainless Steel ◽  
Injection Moulding ◽  
Metal Injection Moulding

Dry Mixing of Feedstock for injection Moulding of 316L Stainless Steel Powder

2012 ◽  
Author(s):  
Mohd. Afian Omar
Keyword(s):  
Stainless Steel ◽  
Injection Moulding ◽  
316L Stainless Steel ◽  
Steel Powder ◽  
Model Material ◽  
Stainless Steel Powder ◽  
Metal Powders ◽  
Wet Process ◽  
Moulding Machine ◽  
Dry Mixing

Bahan pengikat pengacuan yang terdiri daripada polietilina glikol (PEG) dan polimetil metakrilate (PMMA) telah dihasilkan untuk proses pengacuan suntikan logam. Penyediaan bahan suapan adalah secara kaedah basah di mana PMMA adalah dalam bentuk emulsi dengan saiz serbuk antara 0.1 µm hingga 0.2 µm. Oleh itu, untuk menghindarkan proses pengeringan, satu kaedah baru penyediaan bahan suapan dalam bentuk percampuran kering telah dilakukan. Untuk ini, PMMA yang digunakan adalah terdiri daripada serbuk PMMA komersial berjenama Elvacite yang mempunyai saiz serbuk 100 µm dan juga serbuk PMMA yang didapati daripada proses pengeringan emulsi yang dikisar dan diayak hingga ke saiz serbuk 53 µm. Bahan suapan tersebut telah dicampur ke dalam mesin pencampur bilah sigma selama dua jam pada suhu 120°C. Bahan suapan kemudian disemperit panas sebelum dilakukan proses pengacuan. Keputusan uji kaji menunjukkan dalam semua kes, didapati PMMA telah menyerak secara tidak sekata. Ini seterusnya meningkatkan lagi bahan teracu untuk mengampul semasa proses pengurasan dan menyebabkan bahan tersinter mempunyai banyak keliangan. Walau bagaimanapun, adalah dirumuskan bahawa dengan menggunakan serbuk PMMA yang bersaiz lebih kecil, produk yang lebih baik akan diperolehi. Kata kunci: Percampuran kering, pengacuan suntikan logam, pengsinteran, bahan suapan, serbuk keluli tahan karat 316L An injection moulding binder, which is composed of poly ethylene glycols (PEGs) of various molecular weights and poly methylmethacrylate (PMMA), has been developed for injection of metal powders. Feedstocks have been prepared using a wet process with PMMA introduced in the form of an emulsion with particles of 0.1 to 0.2 µm in size. To eliminate the drying process, an attempt has been made to prepare the feedstock using a dry mixing process using 316L stainless steel powder as a model material. For this, the PMMA used was either a commercial powder, Elvacite, with a particle size of up to 100 m or a powder obtained by drying the emulsion and grinding the resultant cake, followed by classification using 53 µm sieves. The feestock constituents were mixed into a sigma blade mixer for 2 hours at mixing temperature of 120°C. The feedstock was then hot extruded using piston injection moulding machine prior to being moulded. It was found in all cases that PMMA was poorly dispersed. This resulted in an increased tendency for the moulded bars to swell on being leached and the sintered bars to have a substantial residual porosity. This study suggests that by using small particles of PMMA powder, an acceptable product could be obtained. Key words: Dry mixing, metal injection moulding, sintering, feedstock, 316L stainless steel powder

Metal injection moulding of scissors using hardenable stainless steel powders

2005 ◽  
Vol 48 (3) ◽  
pp. 227-230 ◽  
Author(s):  
M. A. Newell ◽  
H. A. Davies ◽  
P. F. Messer ◽  
D. J. Greensmith
Keyword(s):  
Stainless Steel ◽  
Injection Moulding ◽  
Metal Injection Moulding
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