Fiber dispersion during compounding/injection molding of PP/kenaf composites: Flammability and mechanical properties

The purpose of this paper is to study the effect of high temperature in injection molding process on mechanical properties of the warp-knitted and nonwoven composite fabrics (WNC)used in car interior. Tensile, tearing and peeling properties of WNC fabrics were tested after heat treatment under120, 140,160,180°C respectively. It was found that, after 140°C heat treatment, the breaking and tearing value of these WNC fabrics are lower than others. The results of this study show that this phenomenon is due to the material properties of fabrics. These high temperatures have no much effect on peeling properties of these WNC fabrics. It is concluded that in order to preserve the mechanical properties of these WNC fabrics, the temperature near 140°C should be avoided possibly during injection molding process.

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Effect of Weld Line Formation on Morphology and Mechanical Properties for 3D-MID Technology

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.659.659 ◽

2015 ◽

Vol 659 ◽

pp. 659-665

Author(s):

Supakit Chuaping ◽

Thomas Mann ◽

Rapeephun Dangtungee ◽

Suchart Siengchin

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Flexural Strength ◽

Injection Molding ◽

Filler Content ◽

Research Work ◽

Weld Line ◽

Processing Conditions ◽

High Reduction ◽

Flexural Tests

The topic of this research work was to demonstrate the feasibility of a 3D-MID concept using injection molding technique and investigate the effects of two weld line types on the structure and mechanical properties such as tensile, flexural strength and morphology. In order to obtain more understanding of the bonds between polymer and metals, two different polymer bases of polyphthalamide (PPA) with the same type and amount of filler content were produced by injection molding at the different processing conditions. A mold was designed in such a way that weld and meld line can be produced with different angles by changing as insert inside of the mold. The mechanical properties such as stiffness, tensile strength and flexural strength were determined in tensile and flexural tests, respectively. The results showed in line with the expectation of high reduction on mechanical properties in area where weld/meld lines occurred. The result of tensile test was clearly seen that weld and meld line showed a considerable influence on mechanical properties. The reduction in tensile strength was approximately 58% according to weld line types, whereas in flexural strength was approximately 62%. On the other hand, the effect of the injection times and mold temperatures on the tensile strength were marginal.

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Post-Processing Time Dependence of Shrinkage and Mechanical Properties of Injection-Molded Polypropylene

Materials ◽

10.3390/ma14010022 ◽

2020 ◽

Vol 14 (1) ◽

pp. 22

Author(s):

Artur Kościuszko ◽

Dawid Marciniak ◽

Dariusz Sykutera

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Injection Molding ◽

Accelerated Aging ◽

Mold Temperature ◽

Degree Of Crystallinity ◽

Injection Mold ◽

Secondary Crystallization ◽

Scanning Calorimetry ◽

Injection Molded

Dimensions of the injection-molded semi-crystalline materials (polymeric products) decrease with the time that elapses from their formation. The post-molding shrinkage is an effect of secondary crystallization; the increase in the degree of polymer crystallinity leads to an increase in stiffness and decrease in impact strength of the polymer material. The aim of this study was to assess the changes in the values of post-molding shrinkage of polypropylene produced by injection molding at two different temperatures of the mold (20 °C and 80 °C), and conditioned for 504 h at 23 °C. Subsequently, the samples were annealed for 24 h at 140 °C in order to conduct their accelerated aging. The results of shrinkage tests were related to the changes of mechanical properties that accompany the secondary crystallization. The degree of crystallinity of the conditioned samples was determined by means of density measurements and differential scanning calorimetry. It was found that the changes in the length of the moldings that took place after removal from the injection mold were accompanied by an increase of 20% in the modulus of elasticity, regardless of the conditions under which the samples were made. The differences in the shrinkage and mechanical properties of the samples resulting from mold temperature, as determined by tensile test, were removed by annealing. However, the samples made at two different injection mold temperature values still significantly differed in impact strength, the values of which were clearly higher for the annealed samples compared to the results determined for the samples immediately after the injection molding.

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Effects of Sintering Variables on the Physical and Mechanical Properties of Metal Injection Molding Molded 17-4 PH Stainless Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1028.403 ◽

2021 ◽

Vol 1028 ◽

pp. 403-408

Author(s):

Apang Djafar Shieddieque ◽

Shinta Virdhian ◽

Moch Iqbal Zaelana Muttahar ◽

Muhammad Rafi Muttaqin

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Injection Molding ◽

Relative Density ◽

Physical And Mechanical Properties ◽

High Hardness ◽

Argon Atmosphere ◽

Metal Injection Molding ◽

Manufacturing Method ◽

Small Complex

Metal injection molding (MIM) is a near net shape manufacturing technique for producing small, complex, precision parts in mass production. MIM process is manufacturing method that combines traditional shape-making capability of plastic injection molding and the materials flexibility of powder metallurgy. The process consists of the following four steps: mixing of metal powder and binder, injection molding to shape the component, debinding to remove the binder in the component, sintering to consolidate the debound parts. In this research, the physical and mechanical properties of metal injection molded 17-4 PH stainless steel were investigated with the variation of sintering temperatures (1300 °C - 1360 °C) and atmosphere conditions (argon and vacuum conditions). The relative density, microstructure, distortion, and hardness are measured and analyzed in this study. The results show that highest relative density of 87%, relative homogeneous shrinkage and high hardness are achieved by sintering at 1360 °C for 1.5 hours and argon atmosphere. At the same sintering temperature and time, sintering in vacuum shows lower relative density (81%) than that in argon condition due to pores growth. The pore growths were not observed in the argon atmosphere. It can be concluded that sintering stages more rapidly under vacuum condition. The hardness measurements result also showed that high hardness is obtained by high density parts. The optimum average hardness obtained in this study is 239 HV. However, the hardness properties results are still lower than 280 HV according to MPIF Standard 35 for MIM parts.

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Mechanical Properties of Injection Molded Rubber Testing Samples

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.752-753.308 ◽

2015 ◽

Vol 752-753 ◽

pp. 308-311

Author(s):

Adam Skrobak ◽

Michal Stanek ◽

David Manas ◽

Martin Ovsik ◽

Vojtech Senkerik ◽

...

Keyword(s):

Mechanical Properties ◽

Injection Molding ◽

Standardized Testing ◽

Rubber Compound ◽

Testing Sample ◽

Synthetic Rubber ◽

Injection Molded

The aim of this article is to demonstrate and asses to what extent there is an impact on the mechanical properties of a standardized testing sample made of rubber compound based on synthetic rubber EPDM and produced by injection molding in comparison with a sample produced by classic preparation (cutting off a compression molded plate) according to the standard ISO 23529.

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Tribology study of hydroxyapatite (HAp) scaffold blended single based binder via rheology and mechanical properties

Industrial Lubrication and Tribology ◽

10.1108/ilt-09-2016-0228 ◽

2017 ◽

Vol 69 (3) ◽

pp. 414-419

Author(s):

Mimi Azlina Abu Bakar ◽

Siti Norazlini Abd Aziz ◽

Muhammad Hussain Ismail

Keyword(s):

Mechanical Properties ◽

Injection Molding ◽

Palm Stearin ◽

Polymeric Materials ◽

High Energy ◽

Single Step ◽

Injection Molding Process ◽

Plastic Behavior ◽

Molding Process ◽

Content Type

Purpose This paper aims to investigate the vital characteristic of an innovative ceramic injection molding (CIM) process for orthopedic application with controlled porosity and improved tribological and mechanical properties which were affected by complex tribological interactions, whether lubricated like hip implants and other artificial prostheses. The main objective is to maximize the usage of palm stearin as a single based binder as the function of flow properties during injection molding process. Design/methodology/approach The binder used in this present study consists of 100 per cent palm stearin manufactured by Kempas Oil Sdn Bhd and supplied by Vistec Technology Sdn Bhd. The feedstock was prepared by using a Z-blade mixer (Thermo Haake Rheomix OS) and Brabender mixer model R2400. The feedstock prepared was injection molded using a manually operated vertical benchtop machine with an average pressure of about 5-7 bars. The firing step included the temporary holds at intermediate temperatures to burn out organic binders. At this stage, the green molded specimen was de-bound using a single-step wick-debinding method. Findings The maximum content of ceramic material is applied to investigate the efficiencies of net formulation that can be achieved by ceramic materials. The longer the viscosity will change with shear rate, the higher the value of n obtained instead. From the slope of the curves obtained in Figure 3, the value of n for the feedstock was determined to be less than 1, which indicates a pseudoplastic behavior and suitability for the molding process. Moreover, high shear sensitivity is important in producing complex and intrinsic specimens which are leading products in the CIM industry. Originality/value The feedstock containing HAp powder and palm stearin binder was successfully prepared at very low temperature of 70°C, which promoting a required pseudo-plastic behavior during rheological test. The single binder palm stearin should be optimized in other research works carried out, as palm stearin is most preferred compared to other polymeric materials that provided high energy consumption when subjected to the sintering process. Besides the binder is widely available in Malaysia, low cost and harmless effect during debinding process.

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Microstructure, Hardness, and Wear Resistance of Powder-Injection-Molded Products of Fe-Based Metamorphic Powders

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.26-28.355 ◽

2007 ◽

Vol 26-28 ◽

pp. 355-358

Author(s):

Chang Kyu Kim ◽

Chang Young Son ◽

Dae Jin Ha ◽

Tae Sik Yoon ◽

Sung Hak Lee

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Wear Resistance ◽

Injection Molding ◽

Powder Injection Molding ◽

Powder Injection ◽

Thermally Stable ◽

Austenitic Matrix ◽

Amorphous Phases ◽

Injection Molded

Powder injection molding (PIM) process was applied to Fe-based metamorphic alloy powders, and microstructure, hardness, and wear resistance of the PIM products were analyzed and compared with those of conventional PIM stainless steel products. When Fe-based metamorphic powders were injection-molded and then sintered at 1200 oC, completely densified products with almost no pores were obtained. They contained 34 vol.% of (Cr,Fe)2B borides dispersed in the austenitic matrix without amorphous phases. Since these (Cr,Fe)2B borides were very hard and thermally stable, hardness, and wear resistance of the PIM products of Fe-based metamorphic powders were twice as high as those of conventional PIM stainless steel products. Such property improvement suggested new applicability of the PIM products of Fe-based metamorphic powders to structures and parts requiring excellent mechanical properties.

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Mechanical Properties of Jute/PLA Injection Molded Products-All Natural Composites

Volume 3: Design and Manufacturing ◽

10.1115/imece2011-62819 ◽

2011 ◽

Cited By ~ 1

Author(s):

Masuo Murakami ◽

Yuqiu Yang ◽

Hiroyuki Hamada

Keyword(s):

Mechanical Properties ◽

Injection Molding ◽

Density Measurement ◽

The Other ◽

Jute Fiber ◽

Poly Lactic Acid ◽

Thermoplastic Polymer ◽

Environmental Friendly ◽

Molding Condition ◽

Natural Composites

Natural composites have been important materials system due to preservation of earth environments. Natural fibers such as jute, hemp, bagasse and so on are very good candidate of natural composites as reinforcements. On the other hand regarding matrix parts thermosetting polymer and thermoplastic polymer deriver form petrochemical products are not environmental friendly material, even if thermoplastic polymer can be recycled. In order to create fully environmental friendly material (FEFM) biodegradable polymer which can be deriver from natural resources is needed. Therefore poly(lactic acid) (PLA) polymer is very good material for the FEFM. However, PLA is very brittle polymer, so that polymer chemists have been made the efforts to make tough PLA. In this paper Jute/PLA composites was fabricated by injection moldings and mechanical properties were measured. It is believable that industries will have much attention to FEFM, so that injection molding was adopted to fabricate the composites. Long fiber pellet pultrusion technique was adopted to prepare jute fiber-PLA pellet (Jute/PLA). Because it is a new method which is able to fabricate composite pellets with relative long length fibers for injection molding process, where, jute yarns were continuously pulled and coated with PLA resin. Here two kinds of PLA materials were used including the one with mold releasing agent and the other is without it. After pass through a heated die whereby PLA resin impregnates into the jute yarns and sufficient cooling, the impregnated jute yarns were cut into pellets. Then Jute/PLA pellets were fed into injection machine to make dumbbell shape specimens. In current study, the effects of temperature of heat die i.e. impregnation temperature and the kind of PLA were focused to get optimum molding condition. The volume fractions of jute fiber in pellet were measured by several measuring method including image analyzing, density measurement and dissolution methods. And the mechanical property were investigated by tensile and Izod testing. It is found that 250 degree is much suitable for Jute/PLA long fiber pultrusion process. Additionally the jute fibers seem much effective to increase the tensile modulus and the Izod strength. That is to say, the addition of Jute fiber in PLA, the brittle property can be improved.

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