Simulation Research of the Effect of Thermal Reflow Processing Parameters on the Profile of Micro-Spherical Structure

2011 ◽  
Vol 239-242 ◽  
pp. 517-523 ◽  
Author(s):  
Bing Yan Jiang ◽  
Lei Chen ◽  
Dai Bing Li ◽  
Stefan Kirchberg
Keyword(s):  
Heating Rate ◽  
Heating Temperature ◽  
Orthogonal Experiment ◽  
Three Dimensional ◽  
Processing Parameters ◽  
Holding Time ◽  
Cylindrical Shape ◽  
Optimum Processing ◽  
Spherical Structure ◽  
Experiment Method

In this paper reflow process is integrated into LIGA process in order to realize three dimensional fabrication. The melting and deformation process of photoresist, which has an initial cylindrical shape of D500μm and h66μm, and the influence of various processing parameters on the height of formed microlens, is simulated with Marc. The optimum processing parameters combination is obtained by orthogonal experiment method and the influence of different processing parameters on the height of micro-spherical structure is studied with single factor experiment method. The results showed that the optimum processing parameters combination was 1°C /s for heating rate, 110°C for heating temperature and 45min for holding time; the significance of processing parameters on the micro-spherical structure’s height can be ordered in holding time＞heating rate＞heating temperature.

Preparation and Properties of Hot Pressed 2D C/SiC Composites

2008 ◽  
Vol 368-372 ◽  
pp. 1047-1049
Author(s):  
Hai Feng Hu ◽  
Feng Zhang ◽  
Qi Kun Wang ◽  
Yu Di Zhang ◽  
Zhao Hui Chen
Keyword(s):  
Carbon Fibers ◽  
Complex Shape ◽  
Sintering Temperature ◽  
Processing Parameters ◽  
Holding Time ◽  
Maximum Strength ◽  
Carbon Powder ◽  
Optimum Processing ◽  
Sic Composites ◽  
Transfer Pressure

In this paper a pseudo-HP process, which uses solid powder to transfer pressure to prepare complex shape articles, was adopted to prepare 2D C/SiC composites. Nano-SiC powder was used to lower the sintering temperature, thus decreasing the damage to carbon fibers. The optimum processing parameters are as follows: sintering temperature 1850°C, holding time 60min, sintering pressure 10MPa. The maximum strength is over 300MPa, and toughness is around 8MPa·m1/2. BN powder is more lubricous than carbon powder, and thus is more convenient for demoulding and pressure transferring. Precursor Infiltration and Pyrolysis (PIP) was used to further densify the composites after HP process, and strength and toughness of the samples were slightly enhanced.

Preparation and Characterization of KGM/CaCO3 Composite Films

2012 ◽  
Vol 724 ◽  
pp. 159-162
Author(s):  
Yan Chen ◽  
Hong Ping Zhang ◽  
Xiao Yan Lin ◽  
Ming Qi Chen ◽  
Yong Man Jiang
Keyword(s):  
Calcium Carbonate ◽  
Zeta Potential ◽  
Orthogonal Experiment ◽  
Composite Films ◽  
Processing Parameters ◽  
Laser Diffraction ◽  
Particle Size Analyzer ◽  
Experiment Method ◽  
Orthogonal Experiment Method

The influences of processing parameters on the tensile strength (TS) of KGM/CaCO3composite films (KCaCF) were investigated through orthogonal experiment method. Calcium carbonate and KCaCF were characterized, respectively, by XRD, laser diffraction particle size analyzer, zeta potential analyzer and SEM. The results showed that micron-sized calcite CaCO3crystals with-16.4 mv of Zeta potential were synthesized. Calcium carbonate dispersion was blended with KGM to fabricate KCaCF. The mass of CaCO3, KGM and swelling time affected TS of composite films differently, but didnt reach the significant level (p>0.05). The optimal preparation process for KCaCF is that 5.0% (wt) of KGM powder is added into the dispersion with 2.0% (wt) of CaCO3, swelling for 1.0 hour at 50 °C and pH 8.0 and then poured onto plate and dried at 50 °C for 15 h.

scholarly journals Fabrication of Miniature Components from ZrO2 Powder by Combining Electrical-field Activated Sintering Technique and Micro-forming

2018 ◽  
Vol 190 ◽  
pp. 10007
Author(s):  
Hasan Hijji ◽  
Yi Qin ◽  
Kunlan Haung ◽  
Muhammad Bin Zulkipli ◽  
Jie Zhao
Keyword(s):  
Low Voltage ◽  
Heating Temperature ◽  
Processing Parameters ◽  
Holding Time ◽  
Micro Forming ◽  
High Quality ◽  
Electrical Field ◽  
Activated Sintering ◽  
Zro2 Powder ◽  
Wide Range

There is an increased demand for miniature/micro products (such as MEMS) and nanotechnology-based products (such as nano-materials). Micro-manufacturing is a link between Macro-and Nano Manufacturing and an effective means for transferring nanotechnology-product designs into volume production. The micro forming has the potential for low-cost, high volume manufacturing applications. In order to meet the high demands on miniaturised products, a rapid production technique and the system, high flexibility, cost-effectiveness and processing a wide range of materials are needed. Recently, a series of studies have been undertaken to investigate forming miniature/micro-components by using a combination of micro-forming and Electrical-field activated sintering (Micro-FAST). The process uses low voltage and high current density, pressure-assisted densification and synthesis technique, which renders several significant merits. The work to be reported in this paper will be focused on the forming of miniature components from Zirconia (ZrO2) powder, without using binders. Several processing parameters have been investigated, such as pressure, heating rate, heating temperature and holding time, which helped to obtain high-quality parts. Using graphite dies and punches, sample parts (solid cylinders of Ø4.00mm × 4.00 mm) were formed. These were subjected to detailed examinations and analysis, such as analysis of the relative density, hardness at the necks formed among the particles and in the particle bodies, as well as the microstructures. The results showed that directly forming the parts from loose powder is feasible, and by properly designing and control the processing parameters, high-quality parts could be achieved, among which heating temperature and holding time are extremely important. At the same time, due to low conductivity of the powder material, carefully designing the tooling is essentials for ensuring properly heating, pressurisation and cooling.

Rapid Development Technology of Mobile Phone Shell Basing on the Selective Laser Sintering

2012 ◽  
Vol 198-199 ◽  
pp. 123-127
Author(s):  
Chong You Feng ◽  
Jin Mei Zhang ◽  
Zheng Yu Zhang ◽  
Li Ping Li
Keyword(s):  
Mobile Phone ◽  
Orthogonal Experiment ◽  
Rapid Development ◽  
Selective Laser Sintering ◽  
Processing Parameters ◽  
Laser Sintering ◽  
Technological Parameters ◽  
Optimum Processing ◽  
Development Technology ◽  
Warpage Deformation

According to the characteristics of mobile phone shell, the mobile phone products model provided by Pro/E software, analyzed the technological parameters of warpage deformation influence, and designed the orthogonal experiment plan, Verified the plan on SINTERSTATION HIQ + HS selective laser sintering system, carried out optimum processing parameters of the minimum warping deformation.

The effect of thermal processing parameters on the mechanical properties of aluminium alloy foam

2018 ◽  
Vol 1 (91) ◽  
pp. 12-17
Author(s):  
D. Puspitasari ◽  
T.L. Ginta ◽  
P. Puspitasari ◽  
M. Mustapha
Keyword(s):  
Mechanical Properties ◽  
Aluminium Alloy ◽  
Thermal Processing ◽  
Heating Temperature ◽  
Processing Parameters ◽  
Holding Time ◽  
Vacuum Furnace ◽  
Closed Cell ◽  
Stress Relieving ◽  
Stabilization Temperature

Purpose: The purpose of this study was to investigate the influence of three thermal processing parameter called stress relieving on mechanical properties of the aluminium alloy foam. Design/methodology/approach: The samples were undergone by stress relieving method using vacuum furnace. Hardness measurement was carried out using microhardness Vickers at 150 mN load and 15 s loading time. Compressive strength, plateau stress and energy absorption were calculated using a universal testing machine. Findings: It was found that the highest value of hardness of 192.78 Hv was obtained when the stress relieving process is set with the following parameters: heating (500°C); holding time (120 min) and stabilization temperature (450°C). Since higher heating temperature and longer holding time produce sample with larger grain size and has an adverse effect on the hardness value It was revealed that the mechanical properties of aluminium alloy foam were enhanced when the heating temperature was decreased, holding temperature was diminished and the stabilization temperature was increased. Overall, the presented results showed that the thermal processing parameters such as heating temperature, holding time and stabilization temperature have a significant influence on improving the mechanical properties of aluminium alloy foam. Research limitations/implications: The properties of closed-cell aluminium alloy foam are highly sensitive and depend on the post heat treatment process. The processing parameters should be controlled in order to manipulate the properties of closed-cell aluminium alloy foam. Originality/value: To investigate the influences of these processing parameters on the physical and mechanical properties of the closed-cell aluminium alloy foam.

The Influence of Processing Parameters on the Surface Integrity of Ni60A Coatings Fabricated by Laser-High Frequency Induction Hybrid Cladding

2016 ◽  
Vol 853 ◽  
pp. 425-430
Author(s):  
Shu Hua Lu ◽  
Xiang Ling ◽  
Jin Chun Zhang
Keyword(s):  
Corrosion Resistance ◽  
High Frequency ◽  
Laser Scanning ◽  
Structural Integrity ◽  
Base Alloy ◽  
Heating Temperature ◽  
Processing Parameters ◽  
Macroscopic Appearance ◽  
Optimum Processing ◽  
High Frequency Induction

The surface of much equipment that employed in petrochemical industry is always damaged by corrosion. As a novel technology, laser-high frequency induction hybrid cladding is an effective surface modification technology. Processing parameters, such as laser power, laser scanning speed and induction heating temperature, play an important part in the structural integrity of the coatings. The effects of these processing parameters to cladding integrity were investigated in this paper. Nickel base alloy (Ni60A) claddings were fabricated on the surface of low alloy steel by the way of laser-high frequency induction hybrid cladding and coaxial powder feeding. Macroscopic appearance and porosity of the claddings were systematically investigated by optical microscopy. The corrosion resistance of specimens manufactured by the optimum processing parameters is evaluated in 3.5% NaCl solution by electrochemical test. As the change of processing parameters, the width, height and porosity of laser claddings had an obvious change. Optimum processing parameters was determined because of the overall performance of the claddings. A good metallurgical bonding between Ni60A claddings and substrate was shown by microstructure. The results of the polarization curves turned out that the corrosion resistance of the Ni60A cladding is apparently better than the matrix.

scholarly journals Optimization of Sintering Process of Alumina Ceramics Using Response Surface Methodology

2021 ◽  
Vol 13 (12) ◽  
pp. 6739
Author(s):  
Darko Landek ◽  
Lidija Ćurković ◽  
Ivana Gabelica ◽  
Mihone Kerolli Mustafa ◽  
Irena Žmak
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Heating Rate ◽  
Sintering Temperature ◽  
Nonlinear Models ◽  
Slip Casting ◽  
Holding Time ◽  
Alumina Ceramics ◽  
Aqueous Suspensions ◽  
Temperature Heating

In this work, alumina (Al2O3) ceramics were prepared using an environmentally friendly slip casting method. To this end, highly concentrated (70 wt.%) aqueous suspensions of alumina (Al2O3) were prepared with different amounts of the ammonium salt of a polycarboxylic acid, Dolapix CE 64, as an electrosteric dispersant. The stability of highly concentrated Al2O3 aqueous suspensions was monitored by viscosity measurements. Green bodies (ceramics before sintering) were obtained by pouring the stable Al2O3 aqueous suspensions into dry porous plaster molds. The obtained Al2O3 ceramic green bodies were sintered in the electric furnace. Analysis of the effect of three sintering parameters (sintering temperature, heating rate and holding time) on the density of alumina ceramics was performed using the response surface methodology (RSM), based on experimental data obtained according to Box–Behnken experimental design, using the software Design-Expert. From the statistical analysis, linear and nonlinear models with added first-order interaction were developed for prediction and optimization of density-dependent variables: sintering temperature, heating rate and holding time.

scholarly journals Mechanical Behavior of Hydroxyapatite-Chitosan Composite: Effect of Processing Parameters

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 213
Author(s):  
Hamid Ait Said ◽  
Hassan Noukrati ◽  
Hicham Ben Youcef ◽  
Ayoub Bayoussef ◽  
Hassane Oudadesse ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Compressive Strength ◽  
Mechanical Strength ◽  
Bone Repair ◽  
Mechanical Stability ◽  
Three Dimensional ◽  
Processing Parameters ◽  
Composite Effect ◽  
Solid Liquid ◽  
The Impact

Three-dimensional hydroxyapatite-chitosan (HA-CS) composites were formulated via solid-liquid technic and freeze-drying. The prepared composites had an apatitic nature, which was demonstrated by X-ray diffraction and Infrared spectroscopy analyses. The impact of the solid/liquid (S/L) ratio and the content and the molecular weight of the polymer on the composite mechanical strength was investigated. An increase in the S/L ratio from 0.5 to 1 resulted in an increase in the compressive strength for HA-CSL (CS low molecular weight: CSL) from 0.08 ± 0.02 to 1.95 ± 0.39 MPa and from 0.3 ± 0.06 to 2.40 ± 0.51 MPa for the HA-CSM (CS medium molecular weight: CSM). Moreover, the increase in the amount (1 to 5 wt%) and the molecular weight of the polymer increased the mechanical strength of the composite. The highest compressive strength value (up to 2.40 ± 0.51 MPa) was obtained for HA-CSM (5 wt% of CS) formulated at an S/L of 1. The dissolution tests of the HA-CS composites confirmed their cohesion and mechanical stability in an aqueous solution. Both polymer and apatite are assumed to work together, giving the synergism needed to make effective cylindrical composites, and could serve as a promising candidate for bone repair in the orthopedic field.

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