Rapid manufacturing of biodegradable pure iron scaffold using amalgamation of three-dimensional printing and pressureless microwave sintering

2018 ◽  
Vol 233 (6) ◽  
pp. 1876-1895 ◽  
Author(s):  
Pawan Sharma ◽  
Pulak M Pandey
Keyword(s):  
Yield Strength ◽  
Sintered Density ◽  
Sintering Temperature ◽  
Microwave Sintering ◽  
Three Dimensional ◽  
Rapid Tooling ◽  
Compressive Yield Strength ◽  
Soaking Time ◽  
Three Dimensional Printing ◽  
Dimensional Printing

In the present work, a rapid tooling process using three-dimensional printing and pressureless microwave sintering has been developed for the fabrication of biodegradable pure iron. Carbonyl iron particles were used for sample preparation and phosphate-based investment material was used for mould fabrication. Cylindrical samples were fabricated successfully using the developed rapid tooling process. The fabrication experiments were planned based on response surface methodology to evaluate the effect of microwave sintering parameters, namely sintering temperature, heating rate and soaking time on sintered density, shrinkage and compressive yield strength. The results showed that sintered density and compressive yield strength increased with the rise in sintering temperature from α to γ iron transformation temperature and were found to decrease with further rise in temperature. The shrinkage was found to increase with the increase in sintering temperature. Moreover, with the increase in soaking time and decrease in heating rate, sintered density, shrinkage and compressive yield strength were found to increase. Scanning electron microscopy and the X-ray diffraction plot of the fabricated iron samples showed that even without the application of pressure proper bonding of carbonyl iron particles was achieved. Mould material contamination or oxidation was not evidenced in the experiments. A multi-objective optimization using genetic algorithm was performed to obtain optimum microwave sintering parameters for maximum sintered density as well as compressive strength and minimum shrinkage. A case study on the fabrication of scaffold for human skull was performed to test the efficacy of the developed rapid tooling process.

An experimental investigation of the fabrication of biodegradable zinc–hydroxyapatite composite material using microwave sintering

2020 ◽  
Vol 234 (14) ◽  
pp. 2863-2880 ◽  
Author(s):  
Dayanidhi Krishana Pathak ◽  
Pulak Mohan Pandey
Keyword(s):  
Yield Strength ◽  
Heating Rate ◽  
Sintered Density ◽  
Sintering Temperature ◽  
Microwave Sintering ◽  
Compaction Pressure ◽  
Optimum Process ◽  
Compressive Yield Strength ◽  
Process Factors

The present work focuses on the fabrication of zinc–hydroxyapatite biodegradable composite with the use of pressureless microwave sintering for the orthopedic load-bearing application. The samples were prepared using the powder metallurgy process. The powders of both materials were homogeneously mixed in the quantified proportions to form the uniform mixture. For the fabrication of samples, the planning of experiments was done with the central composite design. The effect of process factors such as the weight percentage of hydroxyapatite, compaction pressure, and microwave sintering factors such as sintering temperature, heating rate, and soaking time on the compressive yield strength and sintered density was evaluated. Cylindrical samples were prepared for compression testing. The experimental results exhibited the increase in the compressive yield strength as well as the sintered density with the decrease in the hydroxyapatite percentage and an increase in the compaction pressure. The results also revealed that the compressive yield strength and sintered density were found to be increased as the heating rate and sintering temperature increased. Sample characterization was carried out for phase determination and composition of the elements. The optimum process factors were obtained after the regression analysis, and the results of the optimum process factors were also verified with the confirmation experiments. The in vitro corrosion testing of the sample prepared with optimum factors was also carried out in the simulated body fluid at a temperature of 37 ± 0.5 ℃. The fabricated sample showed a good agreement between the mechanical and degradation properties as required for a human bone.

Effect of sintering parameters on the microstructure and compressive mechanical properties of porous Fe scaffold fabricated using 3D printing and pressure less microwave sintering

2020 ◽  
Vol 234 (21) ◽  
pp. 4305-4320
Author(s):  
Dipesh Kumar Mishra ◽  
Pulak Mohan Pandey
Keyword(s):  
Mechanical Properties ◽  
Yield Strength ◽  
Heating Rate ◽  
Sintering Temperature ◽  
Electron Backscatter Diffraction ◽  
Microwave Sintering ◽  
Compressive Yield Strength ◽  
Soaking Time ◽  
Electron Backscatter ◽  
Backscatter Diffraction

The demand for the porous scaffold has been increasing globally in the biomedical field due to numerous advantages over dense structures like high damping capacity, high specific strength, and improved cell integration growth. In the present study, porous iron scaffolds were fabricated using micro-extrusion-based three-dimensional printing and pressureless microwave sintering. For the preparation of samples, metal-based polymeric ink was developed. Thereafter, cylindrical samples were printed and then sintered in a microwave sintering furnace. The experimental investigations were performed to estimate the effect of sintering parameters such as sintering temperature, heating rate and soaking time on the compressive and microstructural property of the fabricated samples. Microstructural characterization was done using the electron backscatter diffraction technique. The experimental observations deduced that the compressive yield strength and apparent density of the sintered sample increased with the increase in sintering temperature and decreased with a further rise in temperature. Moreover, the electron backscatter diffraction analysis unveiled that the high heating rate resulted in the reduction of compressive yield strength due to rapid grain growth. Additionally, the significant effect of soaking time on the compressive mechanical properties was also noticed due to the increase in the grain size diameter. From the X-ray diffraction plot, it was found that there was no contamination present in the fabricated scaffold. In order to evaluate the process capability, a case study was performed wherein the topologically ordered porous structure of iron was fabricated at optimum sintering parameters.

Rapid manufacturing of copper-graphene composites using a novel rapid tooling technique

2020 ◽  
Vol 26 (4) ◽  
pp. 765-776 ◽  
Author(s):  
Gurminder Singh ◽  
Pulak Mohan Pandey
Keyword(s):  
Electrical Conductivity ◽  
Electrical Properties ◽  
Wear Rate ◽  
Coefficient Of Friction ◽  
Rate Coefficient ◽  
Three Dimensional ◽  
Rapid Tooling ◽  
Content Type ◽  
Three Dimensional Printing ◽  
Dimensional Printing

Purpose The purpose of this study is to study the mechanical, tribological and electrical properties of the copper-graphene (Cu-Gn) composites fabricated by a novel rapid tooling technique consist of three-dimensional printing and ultrasonic-assisted pressureless sintering (UAPS). Design/methodology/approach Four different Cu-Gn compositions with 0.25, 0.5, 1 and 1.5 per cent of graphene were fabricated using an amalgamation of three-dimensional printing and UAPS. The polymer 3d printed parts were used to prepare mould cavity and later the UAPS process was used to sinter Cu-Gn powder to acquire free-form shape. The density, hardness, wear rate, coefficient of friction and electrical conductivity were evaluated for the different compositions of graphene and compared with the pure copper. Besides, the comparison was performed with the conventional method. Findings Cu-Gn composites revealed excellent wear properties due to higher hardness, and the lubrication provided by the graphene. The electrical conductivity of the fabricated Cu-Gn composites started increasing initially but decreased afterwards with increasing the content of graphene. The UAPS fabricated composites outperformed the conventional method manufactured samples with better properties such as density, hardness, wear rate, coefficient of friction and electrical conductivity due to homogeneous mixing of metal particles and graphene. Originality/value The fabrication of Cu-Gn composite freeform shapes was found to be difficult using conventional methods. The novel technique using a combination of polymer three-dimensional printing and UAPS as rapid tooling was introduced for the fabrication of freeform shapes of Cu-Gn composites and mechanical, tribological and electrical properties were studied. The method can be used to fabricate optimized complex Cu-Gn structures with improved wear and electrical applications.

3D Printing of Calcia-Based Ceramic Core Composites

2014 ◽  
Vol 88 ◽  
pp. 65-69
Author(s):  
Huo Ping Zhao ◽  
Chun Sheng Ye ◽  
Zi Tian Fan
Keyword(s):  
Bending Strength ◽  
Sintering Temperature ◽  
Three Dimensional ◽  
Fabrication Process ◽  
Ceramic Core ◽  
Three Dimensional Printing ◽  
Freeform Fabrication ◽  
Ceramic Components ◽  
Hydration Resistance ◽  
Dimensional Printing

Three-dimensional printing has been used as a rapid freeform fabrication process to fabricate a wider range of green ceramic components with complex structures difficult to obtain using traditional ceramic fabrication process. In this study, calcia-based ceramic core composites were fabricated by three dimensional printing and sintering operation. The green bodies were printed using a CaO/TiO2powder mixture as a precursor material and ethylene glycol as a binder. They were sintered at 1400-1500 °C for 2 h. The phases and microstructures of these samples were characterized by X-ray diffraction and scanning electron microscopy. The effect of TiO2content and the sintering temperature on the density, hydration resistance and bending strength of the sintered bodies was investigated. It was found that increment of TiO2content and sintering temperature would result in an increase of density of the sintered bodies and then increase of hydration resistance and bending strength.

Development, evaluation, and selection of rapid tooling process chains for sand casting of functional prototypes

2007 ◽  
Vol 221 (9) ◽  
pp. 1441-1450 ◽  
Author(s):  
D Dimitrov ◽  
W van Wijck ◽  
N de Beer ◽  
J Dietrich
Keyword(s):  
Three Dimensional ◽  
Rapid Tooling ◽  
Sand Casting ◽  
Printing Process ◽  
Three Dimensional Printing ◽  
Core Technology ◽  
Process Chains ◽  
Accuracy And Repeatability ◽  
Dimensional Printing ◽  
Selection Of

This paper discusses the results obtained from studies on different rapid tooling process chains for improved design and manufacture of foundry equipment for sand casting of prototypes in final material for functional and pre-production tests of vehicles, using the three-dimensional printing process as core technology. Subsequently, while considering aspects such as time, cost, quality (accuracy and surface roughness), and tool life, a framework for evaluation and selection of the most suitable process chain in accordance to specific requirements is presented. Apart from only using these process chains for prototype manufacturing, initial results from a study to apply one of these process chains in automated sand casting full production is also presented. This research builds on an in-depth characterization of the accuracy and repeatability of a three-dimensional printing process.

Experimental Investigation Into the Fabrication of Porous Biodegradable Fe Scaffold by Microwave Sintering of 3D Printed Green Body

2021 ◽  
Author(s):  
Dipesh Kumar Mishra ◽  
Pulak Mohan Pandey
Keyword(s):  
Porous Structure ◽  
Microwave Sintering ◽  
Three Dimensional ◽  
The Body ◽  
Compressive Yield Strength ◽  
Electron Microscopic ◽  
Biodegradable Implant ◽  
Three Dimensional Printing ◽  
Sem Image ◽  
Design Structure

Abstract Iron has appealing biodegradable properties that makes compatible for biodegradable implant tools applications. Although, the slow corrosion rate of Fe made obsolete for biomedical applications. The incorporation of the porous structure may result in an enhanced degradation rate. The main advantage offer by the porous structure is to allow to flow the body transportation fluid through it and ease to proliferate the new tissue. Therefore, the current work focused on the development of a porous Fe structures using micro-extrusion based three-dimensional printing (ME3DP) and pressure less microwave sintering. The metallic-based polymeric ink used to fabricate the intent design structure. Subsequently, samples were heated in the microwave sintering furnace. The experimentations were done to evaluate the outcomes of different Fe concentrations (91–95 wt.%) on density and compressive yield strength of developed porous parts. Experimental observation deduced that fabricated part ≥ 94.wt.% of Fe concentration has strong bonding strength between the printed layers. Moreover, the mechanical property of 94 wt.% has found greater than 95 wt.% of Fe concentration. The scanning electron microscopic (SEM) image illustrated the presence of porous morphology into the fabricated body. Additionally, XRD (X-ray diffraction) plots exhibited the purity of sample without any contamination residue.

Investigating the relation between debinding atmosphere and mechanical properties of stereolithography-based three-dimensional printed Al2O3 ceramic

2020 ◽  
Vol 234 (14) ◽  
pp. 1686-1694 ◽  
Author(s):  
He Li ◽  
Yongsheng Liu ◽  
Yansong Liu ◽  
Kehui Hu ◽  
Zhigang Lu ◽  
...  
Keyword(s):  
Flexural Strength ◽  
Crystallite Size ◽  
Sintering Temperature ◽  
Three Dimensional ◽  
Oxidation Reactions ◽  
Three Dimensional Printing ◽  
Air Atmosphere ◽  
Ultraviolet Curable ◽  
Debinding Process ◽  
Dimensional Printing

Ceramic green bodies fabricated by stereolithography-based three-dimensional printing technology often have high loading of ultraviolet curable resins, which produce undesirable phenomena such as cracking, deformation, and blistering during the debinding process. Results showed that compared to argon and vacuum, air atmosphere provided higher flexural strength owing to the elevated density. The differences in microstructure between specimens prepared under these atmospheres were attributed to exothermic oxidation reactions occurred under air when compared to endothermic pyrolysis reactions under vacuum and argon. The debinding atmosphere showed little effect on crystallite size due to the elevated sintering temperature, which would determine the final crystallite size of Al2O3. Debinding under air atmosphere resulted in flexural strength of 176.69 MPa and open porosity of 23.4%. The flexural strength of the ceramics debinded in air was 21.6% higher than the ceramics debinded in argon atmosphere.

Three Dimensional Printing of Titanium for Bone Tissue Engineering Applications: A Preliminary Study

2014 ◽  
Vol 21 ◽  
pp. 101-115 ◽  
Author(s):  
Vipra Guneta ◽  
Jun Kit Wang ◽  
Saeed Maleksaeedi ◽  
Ze Ming He ◽  
Marcus Thien Chong Wong ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Computer Aided Design ◽  
Sintering Temperature ◽  
Three Dimensional ◽  
Patient Specific ◽  
Three Dimensional Printing ◽  
Native Bone ◽  
Dimensional Printing

One of the main goals of bone tissue engineering is the development of scaffolds that mimic both functional and structural properties of native bone itself. This study describes the preliminary work carried out to assess the viability of using three dimensional printing (3DP) technology for the fabrication of porous titanium scaffolds with lowered modulus and improved biocompatibility. 3DP enables the manufacturing of three dimensional (3D) objects with a defined structure directly from a Computer Aided Design (CAD). The overall porosity of the 3D structures is contributed by the presence of both pores-by-process (PBP) and pores-by-design (PBD). This study mainly focuses on the PBP, which are formed during the sintering step as the result of the removal of the binding agent polyvinyl alcohol (PVA). Sintering temperatures of 1250oC, 1350oC and 1370oC were used during the fabrication process. Our results showed that by varying the binder percentage and the sintering temperature, pores with diameters in the range of approximately 17-24 μm could be reproducibly achieved. Other physical properties such as surface roughness, porosity and average pore size were also measured for all sample groups. Results from subsequent cell culture studies using adipose tissue-derived mesenchymal stem cells (ASCs) showed improved attachment, viability and proliferation for the 3DP titanium samples as compared to the two-dimensional (2D) dense titanium samples. Hence, based on our current preliminary studies, 3DP technology can potentially be used to fabricate customized, patient-specific metallic bone implants with lowered modulus. This can effectively help in prevention of stress-shielding, and enhancement of implant fixationin vivo. It is envisioned that an optimized combination of binder percentage and sintering temperature can result in the fabrication of scaffolds with the desired porosity and mechanical properties to fit the intended clinical application.

Sign in / Sign up

Export Citation Format

Share Document