Near-net shaping of silicon nitride via aqueous room-temperature injection molding and pressureless sintering

2017 ◽  
Vol 43 (14) ◽  
pp. 10791-10798 ◽  
Author(s):  
Lisa M. Rueschhoff ◽  
Rodney W. Trice ◽  
Jeffrey P. Youngblood
Keyword(s):  
Silicon Nitride ◽  
Injection Molding ◽  
Room Temperature ◽  
Pressureless Sintering ◽  
Near Net Shaping ◽  
Net Shaping

Gelcasting of Stainless Steel Powder: An Alternative to Injection Molding

2010 ◽  
Vol 660-661 ◽  
pp. 194-199 ◽  
Author(s):  
Fernando dos Santos Ortega ◽  
R.L.S. Oliveira ◽  
M.C. Plínio ◽  
Bernardo N. Nobrega
Keyword(s):  
Stainless Steel ◽  
Injection Molding ◽  
Low Cost ◽  
Steel Powder ◽  
Surface Finishing ◽  
Powder Injection ◽  
Good Surface ◽  
High Solids Loading ◽  
Near Net Shaping ◽  
Net Shaping

The gelcasting process is a forming technique originally developed for the shaping of advanced ceramics into final products in attempts to overcome some of the limitations of conventional forming techniques used in powder metallurgy. It is based on preparing a high solids loading suspension of powder dispersed in an aqueous organic monomers solution, which is poured into a mold and gelled through a chemically initiated polymerization. This work describes the gelcasting of HK-30 stainless steel, a type of powder commonly processed by injection molding. Large (70 x 30 mm) and geometrically complex green compacts with outstanding form retention and stability were obtained. Sintered parts showed good surface finishing and reached 96% of theoretical density, yield strength of 418.5 MPa, and ultimate strength of 701.5 MPa. These results compare favorably with those typically obtained through conventional powder injection molding of HK-30 feedstocks. They support the growing view that gelcasting may soon become an industrial, low cost alternative for near net shaping metallic powders into small or large parts with complex geometries

scholarly journals Microstructure Evolution of (MgCoNiZnCu)O High Entropy Oxides Using Ceramic Injection Molding

2021 ◽  
Author(s):  
Yipeng ZHAO ◽  
Guoqing CHEN ◽  
Hongwei LI ◽  
Xuesong FU ◽  
Wenlong ZHOU
Keyword(s):  
Injection Molding ◽  
Injection Molding Process ◽  
Molding Process ◽  
High Entropy ◽  
Ceramic Injection Molding ◽  
Oxide Powders ◽  
Shaping Process ◽  
Thermal Debinding ◽  
Near Net Shaping ◽  
Net Shaping

Abstract Near net shaping ceramic injection molding process of (MgCoNiZnCu)O high entropy oxides were conducted using commercial precursor oxide powders. Through ball milling, internal mixing, injection molding, solvent and thermal debinding as well as final sintering process, the ceramic products would be obtained with little machining. Compacts prepared are single rock-salt phase based on XRD and EDS Mapping results. Meanwhile, with the increasing of sintering temperature from 900 ℃ to 1050 ℃, particle diffusion rate and densification of samples becomes faster, which finally results relative density and fractured strength of sintered compacts reaching the highest (90.47 % and 77.98 MPa, respectively) in current work. The successfully synthesis of (MgCoNiZnCu)O through ceramic injection molding illustrates this near net shaping process could be a promising route for preparation of high entropy oxides.

Near Net Shaping of Monolithic and Composite MAX Phases by Injection Molding

2016 ◽  
Vol 99 (10) ◽  
pp. 3210-3213 ◽  
Author(s):  
Jesus Gonzalez-Julian ◽  
Lukas Classen ◽  
Martin Bram ◽  
Robert Vaßen ◽  
Olivier Guillon
Keyword(s):  
Injection Molding ◽  
Max Phases ◽  
Near Net Shaping ◽  
Net Shaping

Fabrication and Testing of Ceramic Turbine Wheels

1991 ◽  
Author(s):  
K. Takatori ◽  
T. Honma ◽  
N. Kamiya ◽  
H. Masaki ◽  
S. Sasaki ◽  
...  
Keyword(s):  
Silicon Nitride ◽  
Injection Molding ◽  
Room Temperature ◽  
Cold Isostatic Pressing ◽  
Inlet Temperature ◽  
Outer Diameter ◽  
Turbine Inlet Temperature ◽  
Binder Removal ◽  
Design Speed ◽  
Free Body

Silicon nitride (Si3N4) radial inflow turbine wheels were fabricated by injection molding at Toyota Central R & D Labs. The wheel was 142mm in outer diameter and had 14 blades. The radial wheel was too bulky to manufacture as a homogeneous and defect-free body in one piece. It was divided into two pieces for injection molding and put together into one body by a cold isostatic pressing step after binder removal. Spin testing was executed at room temperature and the resulting photographs taken from three directions provided useful information about the fracture mode of the wheels. The maximum burst speed of the wheels at room temperature was 98,900 rpm, which corresponded to 145% of the design speed. In a hot rig test, one of the wheels survived 75,000rpm for ten minutes at a turbine inlet temperature of 1,050°C.

Electrical and Optical Properties of Si+ and P+ Implanted InP:Fe

1990 ◽  
Vol 201 ◽  
Author(s):  
Honglie Shen ◽  
Genqing Yang ◽  
Zuyao Zhou ◽  
Guanqun Xia ◽  
Shichang Zou
Keyword(s):  
Optical Properties ◽  
Silicon Nitride ◽  
Temperature Dependence ◽  
Optimal Condition ◽  
Room Temperature ◽  
Broad Band ◽  
Photoluminescence Spectra ◽  
Electrical And Optical Properties ◽  
Spectrum Measurement ◽  
Single Implant

AbstractDual implantations of Si+ and P+ into InP:Fe were performed both at 200°C and room temperature. Si+ ions were implanted by 150keV with doses ranging from 5×1013 /cm2 to 1×1015 /cm2, while P+ ions were implanted by 110keV. 160keV and 180keV with doses ranging from 1×l013 /cm2 to 1×1015 /cm2. Hall measurements and photoluminescence spectra were used to characterize the silicon nitride encapsulated annealed samples. It was found that enhanced activation can be obtained by Si+ and P+ dual implantations. The optimal condition for dual implantations is that the atomic distribution of implanted P overlaps that of implanted si with the same implant dose. For a dose of 5×l014 /cm2, the highest activation for dual implants is 70% while the activation for single implant is 40% after annealing at 750°C for 15 minutes. PL spectrum measurement was carried out at temperatures from 11K to 100K. A broad band at about 1.26eV was found in Si+ implanted samples, of which the intensity increased with increasing of the Si dose and decreased with increasing of the co-implant P+ dose. The temperature dependence of the broad band showed that it is a complex (Vp-Sip) related band. All these results indicate that silicon is an amphoteric species in InP.

Phase Relationship Studies of Silicon Nitride System—A Key to Materials Design

1992 ◽  
Vol 287 ◽  
Author(s):  
T.S. Yen ◽  
W.Y. Sun
Keyword(s):  
Elevated Temperature ◽  
Silicon Nitride ◽  
Grain Boundary ◽  
Phase Behavior ◽  
Phase Diagrams ◽  
Room Temperature ◽  
Phase Relationship ◽  
Materials Design ◽  
Basic Approach ◽  
System A

ABSTRACTAdditions and revisions to several of the most important phase diagrams and phase behavior diagrams in the silicon nitride field are reviewed in this work, with emphasis on the Y-Si-A1-O-N system. This information is further used to make observations on the promising silicon nitride systems containing either highly refractory grain boundary phases or compatible matrix phases of desirable properties. Examples are provided to illustrate the advantage of such a basic approach to materials design. Hardness, toughness, strength at room temperature and elevated temperature and even sinterability can all be improved by adopting such an approach.

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