Characterization of Micro Metal Injection Molding by Using PMMA & PEG

2013 ◽  
Vol 315 ◽  
pp. 992-996
Author(s):  
Mohd Halim Irwan Ibrahim ◽  
Norhamidi Muhamad ◽  
A.B. Sulong
Keyword(s):  
Stainless Steel ◽  
Injection Molding ◽  
Injection Pressure ◽  
Steel Powder ◽  
Mold Temperature ◽  
Point Of View ◽  
Metal Injection Molding ◽  
Volume Percentage ◽  
Shape Retention ◽  
Injection Temperature

Due to its versatility, micro metal injection molding has become an alternative method in powder metallurgy where it can produce small part with a minimal number of waste. The success of micro MIM is greatly influenced by feedstock characteristics. This paper investigated the characterization and optimization which both of them plays an important characteristic in determining the successful of micro MIM. In this paper, stainless steel SS 316L was used with composite binder, which consists of PEG (Polyethelena Glycol), PMMA (Polymethyl Methacrilate) and SA (Stearic Acid). The rheology properties are investigated using Shimadzu Flowtester CFT-500D capillary rheometer. The geometry of water atomised stainless steel powder are irregular shape, therefore it is expected significant changes in the rheological results that can influence the microcomponent, surface quality, shape retention and resolution capabilities. From rheological characteristics, feedstock with 61.5% shows a significant value with several injection parameters were optimized through screening experiment such as injection pressure (A), injection temperature (B), mold temperature (C), injection time (D) and holding time (E). Besides that, interaction effects between injection pressure, injection temperature and mold temperature were also considered to optimize in the Taguchis orthogonal array. Result shows that 61.5%vol contributes a significant stability over a range of temperature and the best powder loading from a critical powder volume percentage (CPVP) and rheological point of view. Furthermore interaction between injection temperature and mold temperature (BxC) give highest significant factor followed by interaction between injection pressure and mold temperature (AxC).

Optimization of Injection Parameters Using 16µm Stainless Steel Powder (SS316L) at 63 Vol. %, 63.5 Vol. % and 64 Vol. % Powder Loading by Taguchi Method for Metal Injection Molding

2011 ◽  
Vol 471-472 ◽  
pp. 558-562 ◽  
Author(s):  
Muhammad Ilman Hakimi Chua Abdullah ◽  
Abu Bakar Sulong ◽  
Norhamidi Muhamad ◽  
Mohd Fazuri Abdullah ◽  
Che Hassan Che Haron
Keyword(s):  
Stainless Steel ◽  
Injection Molding ◽  
Surface Quality ◽  
Injection Pressure ◽  
Steel Powder ◽  
Mold Temperature ◽  
Stainless Steel Powder ◽  
Holding Time ◽  
Metal Injection Molding ◽  
Injection Temperature

In this paper, injection molding parameters are optimized using the L18 Taguchi orthogonal array for mechanical strength and surface quality of the green part. The feedstock used consists of stainless steel powder (SS316L) with the powder loading of 63 vol. %, 63.5 vol. % & 64 vol. %. The binder compositions used are polyethelene glycol (PEG-73 wt.%), polymethyl methacrilate (PMMA-25 wt.%) and stearic acid (4 wt.%). Mould temperature, injection temperature, injection pressure, injection time, holding time and powder loading ware selected as signal factors using Taghuci’s method based on literature, where these parameters were significant in MIM. Results showed that the optimum parameters are: mold temperature at 650C, injection temperature at1450C, injection pressure at 650 bar, injection flow rate at 20 m3/s, holding time at 5 s and powder loading of 64 vol.%. Analysis of Variance (ANOVA) result shown that mold temperature is the most influence in order to produce good green part’s surface quality while powder loading give the best result for green part’s strength.

Rheological Characterization of Water Atomised Stainless Steel SS316L for Micro MIM

2011 ◽  
Vol 264-265 ◽  
pp. 129-134 ◽  
Author(s):  
Mohd Halim Irwan Ibrahim ◽  
Norhamidi Muhamad ◽  
Abu Bakar Sulong
Keyword(s):  
Stainless Steel ◽  
Flow Behavior ◽  
Steel Powder ◽  
Point Of View ◽  
Stainless Steel Powder ◽  
Metal Injection Molding ◽  
Rheological Characterization ◽  
Volume Percentage ◽  
Power Loading ◽  
Shape Retention

This paper investigates the performance of feedstock characteristics for micro metal injection molding (μMIM) by using optimum power loading variation and rheological characterization. The study has been emphasized on the powder and binder system in which stainless steel SS316L powder are mixed with composite binder, which consists of PEG (Polyethelena Glycol), PMMA (Polymethyl Methacrilate) and SA (Stearic Acid) by variation of powder loading concentration. The rheology properties are investigated using Shimadzu Flowtester CFT-500D capillary rheometer. As the geometry of water atomised stainless steel powder are irregular shape, therefore it is expected significant changes in the rheological results that can influence the microcomponent, surface quality, shape retention and resolution capabilities. The optimization of the μMIM rheological properties as a function of stainless steel powder loading concentration are evaluated by flow behavior exponent, activation energy and moldability index. From the results, it shows that 61.5%vol contributes a significant stability over a range of temperature and the best powder loading from a critical powder volume percentage (CPVP) and rheological point of view.

Optimization of Micro Metal Injection Molding SS 316L for the Highest Green Strength by Using Taguchi Method

2011 ◽  
Vol 264-265 ◽  
pp. 135-140 ◽  
Author(s):  
Mohd Halim Irwan Ibrahim ◽  
Norhamidi Muhamad ◽  
Abu Bakar Sulong ◽  
Khairur Rijal Jamaludin ◽  
Nor Hafiez Mohamad Nor ◽  
...  
Keyword(s):  
Injection Molding ◽  
Taguchi Method ◽  
Injection Pressure ◽  
Rheological Characteristic ◽  
Mold Temperature ◽  
Metal Injection Molding ◽  
Small Scale ◽  
Injection Time ◽  
Green Strength ◽  
Injection Temperature

Micro metal injection molding which is a new develop technology has attract most researcher where it becomes among the promising method in powder metallurgy research to produce small-scale intricate part at an effective process and competitive cost for mass production. Due to highly stringent characteristics of micro MIM feedstock,the study has been emphasized in investigating the optimization of highest green strength which plays an important characteristic in determining the successful of micro MIM. Stainless steel SS 316L with D50 = 5.96μm was used with composite binder, which consists of PEG, PMMA and Stearic Acid. From rheological characteristic and highly significant parameter through screening experiment, feedstock with 61.5% with several injection parameters were optimized such as injection pressure(A), injection temperature(B), mold temperature(C), injection time(D) and holding time(E). Besides that, interaction effects between injection pressure, injection temperature and mold temperature were also considered to optimize in the Taguchi’s orthogonal array. Analysis of variance (ANOVA) in terms of signal-to-noise ratio (S/N-larger is better) for green strength was also presented in this paper. Result shows that interaction between injection temperature and mold temperature(BxC) give highest significant factor followed by interaction between injection pressure and injection temperature(AxB). Single factor that also contributes to significant optimization are mold temperature(C), injection time(D) and injection pressure(A). This study shows that Taguchi method would be among the best method to solve the problem with minimum number of trials.

Application of Taguchi Method for Parameters Optimization in Micro Metal Injection Molding

2011 ◽  
Vol 52-54 ◽  
pp. 244-248
Author(s):  
Haw Pei Li ◽  
Norhamidi Muhamad ◽  
Abu Bakar Sulong ◽  
Heng Shye Yunn ◽  
Hooman Abolhasani
Keyword(s):  
Injection Molding ◽  
Signal To Noise Ratio ◽  
Steel Powder ◽  
Mold Temperature ◽  
Parameters Optimization ◽  
Simultaneous Optimization ◽  
Metal Injection Molding ◽  
Surface Appearance ◽  
Optimal Injection ◽  
Acetate Butyrate

Optimization of injection parameters in Micro Metal Injection Molding (μMIM) was described in this study. Stainless steel powder was mixed with Polyethelena Glycol (PEG), Polymethyl Methacrilate (PMMA) and Cellulose Acetate Butyrate (CAB) to produce feedstock. Design of Experiments (DOE) of Taguchi L-27 (313) orthogonal array technique has been used to investigate the significance and optimal injection molding parameters. The signal-to-noise ratio and analysis of variance (ANOVA) are applied to study the optimum levels and effects of process parameters. Simultaneous optimization to obtain the highest green density and excellent surface appearance was discussed. The result concluded that the mold temperature (D) is the most statistically significant process parameter and its contribution to the best appearance and density is the highest.

scholarly journals Study on Stability of a Novel Binder System Based on Palm Stearin in Metal Injection Moulding Application

2007 ◽  
Vol 4 (2) ◽  
pp. 1
Author(s):  
Muhammad Hussain Ismail ◽  
Norhamidi Muhamad ◽  
Aidah Jumahat ◽  
Istikamah Subuki ◽  
Mohd Afian Omar
Keyword(s):  
Injection Molding ◽  
Flow Characteristics ◽  
Injection Pressure ◽  
Palm Stearin ◽  
Steel Powder ◽  
Metal Injection Molding ◽  
Injection Molding Process ◽  
Binder System ◽  
Molding Process ◽  
Flow Activation Energy

Metal Injection Molding (MIM) is a wellestablished technology for manufacturing a variety of complex and small precision parts. In this paper, fundamental rheological characteristics of MIM feedstock using palm stearin are theoretically analyzed and presented. The feedstock consisted of gas atomized 316L stainless steel powder at three different particle size distributions and the binder system of palm stearin (PS) and polyethylene (PE). The powder loading used was 60vol % for all samples (monosize 16 µm, monosize 45 µm, and bimodal 16 µm + 45 µm) and the binder system of 40vol %(PS/PE = 40/60). The viscosity of MIM feedstock at different temperatures and shear rates was measured and evaluated. Results showed that, the feedstock containing palm stearin exhibited suitable rheological properties by increasing the fluidity of feedstock in MIM process. The rheological results also showed a pseudoplastic flow characteristics, which poses higher value of shear sensitivity (n) and lower value of flow activation energy (E), that are both favourable for injection molding process. The green parts were successfully injected and exhibited adequate strength for handling by optimizing the injection pressure and temperature.

Mixing and Characterisation of Stainless Steel 316L Feedstock for Waste Polystyrene Binder System in Metal Injection Molding (MIM)

2014 ◽  
Vol 607 ◽  
pp. 83-86 ◽  
Author(s):  
Rosli Asmawi ◽  
Mohd Halim Irwan Ibrahim ◽  
Azriszul Mohd Amin
Keyword(s):  
Stainless Steel ◽  
Injection Molding ◽  
Palm Kernel ◽  
Steel Powder ◽  
Metal Injection Molding ◽  
Binder System ◽  
Stainless Steel 316L ◽  
Palm Kernel Oil ◽  
Kernel Oil ◽  
Waste Polystyrene

This paper describes the mixing process and homogeneity analysis of a newly developed binder system based on waste polystyrene (PS) and palm kernel oil (PKO) to produce feedstock for metal injection molding (MIM). Since mixing is a critical step in MIM process, hence the mixture of powder and binder should be homogeneous and injectable. In this study, water atomised Stainless Steel powder was mixed with a new binder system consisting of waste polystyrene and palm kernel oil in a Brabender Plastograph EC rotary mixer. Several tests were performed to assess the homogeneity of the feedstock that was produced at 60 vol.% powder loadings. The 60 vol.% was chosen because the Critical Powder Volume Concentration (CPVC) of the SS316L powder was found to be 64.8 vol.%. The tests conducted were density, binder burn-out and SEM morphology observation. It was found that the feedstock shows good homogeneity and suitable for further processing in MIM.

scholarly journals Study on Stability of a Novel Binder System Based on Palm Stearin in Metal Injection Moulding Application

2007 ◽  
Vol 4 (2) ◽  
pp. 1 ◽  
Author(s):  
Muhammad Hussain Ismail ◽  
Norhamidi Muhamad ◽  
Aidah Jumahat ◽  
Istikamah Subuki ◽  
Mohd Afian Omar
Keyword(s):  
Injection Molding ◽  
Flow Characteristics ◽  
Injection Pressure ◽  
Palm Stearin ◽  
Steel Powder ◽  
Metal Injection Molding ◽  
Injection Molding Process ◽  
Binder System ◽  
Molding Process ◽  
Flow Activation Energy

Metal Injection Molding (MIM) is a wellestablished technology for manufacturing a variety of complex and small precision parts. In this paper, fundamental rheological characteristics of MIM feedstock using palm stearin are theoretically analyzed and presented. The feedstock consisted of gas atomized 316L stainless steel powder at three different particle size distributions and the binder system of palm stearin (PS) and polyethylene (PE). The powder loading used was 60vol % for all samples (monosize 16 µm, monosize 45 µm, and bimodal 16 µm + 45 µm) and the binder system of 40vol %(PS/PE = 40/60). The viscosity of MIM feedstock at different temperatures and shear rates was measured and evaluated. Results showed that, the feedstock containing palm stearin exhibited suitable rheological properties by increasing the fluidity of feedstock in MIM process. The rheological results also showed a pseudoplastic flow characteristics, which poses higher value of shear sensitivity (n) and lower value of flow activation energy (E), that are both favourable for injection molding process. The green parts were successfully injected and exhibited adequate strength for handling by optimizing the injection pressure and temperature.

Designs and Evaluations of a Gas Atomizer to Fabricate Stainless Steel Metal Powder to Be Applied at a Metal Injection Molding

2020 ◽  
Vol 833 ◽  
pp. 40-47 ◽  
Author(s):  
Sugeng Supriadi ◽  
Tsaome Indah Susimah ◽  
Muhammad Haekal Sena Akbar ◽  
Bambang Suharno ◽  
Ario Sunar Baskoro ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Injection Molding ◽  
Metal Powder ◽  
Spherical Shape ◽  
Steel Powder ◽  
Gas Pressure ◽  
Metal Injection Molding ◽  
Powder Morphology ◽  
Melt Flow Rate ◽  
Significant Difference

Metal Injection Molding (MIM) is an application of Powder Metallurgy (PM) and Plastic Injection Molding currently being developed to produce precisely-small components. Most of the metal applications using PM are stainless steel fabricated by a gas atomizer. In this study, an atomizer is designed and fabricated to produce stainless steel powder by using a free fall gas atomization method. The stainless steel used in this study is AISI 304 atomized with the diameter sizes varying from about 3 mm, 5 mm, and 7 mm. The variables of diameter size results are the lowest melt flow rate produces the smallest mean diameter, but no significant difference on the sphericity of powder morphology. While the gas pressure variation results shows that metal powder with smaller size will be produced more using the high gas pressure. The gas atomizer have successfully produced metal powder with the size <40 μm and have a spherical shape. The well rounded sphericity for melt flowrate 0.41x10-3 m3/min, 1.14 x10-3 m3/min, and 2.24x10-3 m3/min are 60.0%, 36.0%, and 55.2% respectively.

Determination of Optimal Microminiature Powder Injection Molding Parameters by Taguchi Approach

2011 ◽  
Vol 189-193 ◽  
pp. 2997-3000
Author(s):  
Haw Pei Li ◽  
Norhamidi Muhamad
Keyword(s):  
Stainless Steel ◽  
Injection Molding ◽  
High Performance ◽  
Injection Pressure ◽  
Steel Powder ◽  
Powder Injection Molding ◽  
Powder Injection ◽  
Injection Molding Process ◽  
Taguchi Approach ◽  
Molding Process

The global manufacturing trend is now focusing towards miniaturization. Microminiature Powder Injection Molding (μPIM) is a viable technology to fabricate complex and high performance miniaturized components. The μPIM technique was used to produce the near-net shape micro components in this study. Fine stainless steel powder with particle size of 5μm was mixed with a ternary water-based binder system. Micro dumbbells with the largest dimension of 9mm were replicated. In order to obtain successful and well molded micro dumbbells, the Design of Experiments (DOE) technique was applied to investigate the optimal parameters in injection molding process. Injection parameters such as injection pressure (A), injection temperature (B), powder loading (C), mold temperature (D), injection time (E) and holding time (F) were optimized by using stainless steel feedstocks. Taguchi approach is chosen and the results were evaluated with signal-to-noise (SN) ratio and analysis of variance (ANOVA). The results show that the feedstocks could be replicated by using μPIM method with the application of Taguchi approach.

Sign in / Sign up

Export Citation Format

Share Document