scholarly journals Influence of applied pressure on the microstructure and properties of Ti(C,N)–TiB2–Co cermets prepared in situ by reactive hot-pressing

2016 ◽  
Vol 124 (10) ◽  
pp. 1116-1122 ◽  
Author(s):  
Xianrui ZHAO ◽  
Dunwen ZUO ◽  
Mengxian ZHANG ◽  
Feng XU ◽  
Shangshen FENG
Keyword(s):  
Hot Pressing ◽  
Applied Pressure ◽  
Microstructure And Properties ◽  
Reactive Hot Pressing

Reactive hot pressing of aluminum matrix composites

1999 ◽  
Vol 14 (11) ◽  
pp. 4246-4250
Author(s):  
H. J. Brinkman ◽  
J. Duszczyk ◽  
L. Katgerman
Keyword(s):  
Hot Pressing ◽  
Adverse Reactions ◽  
Aluminum Matrix ◽  
Aluminum Matrix Composites ◽  
Matrix Composites ◽  
Processing Step ◽  
Exothermic Process ◽  
Composite Product ◽  
Reactive Hot Pressing

A method is described for the production of dense aluminum matrix composites from elemental powders in one processing step by reactive hot pressing (RHP). It encompasses both the exothermic conversion of reactants to composite product and the following hot compaction of the porous composite product. The RHP method described in this paper takes into account the gas evolution accompanying the exothermic process, ensures complete conversion of reactants, and avoids adverse reactions between aluminum matrix and graphite tooling material. In situ sample temperature measurements enable proper process control, in particular the timing of the full densification step of the hot reaction product.

Reaction Synthesized Boron Nitride-Containing Composites (BNCC)

2007 ◽  
Vol 280-283 ◽  
pp. 1385-1390
Author(s):  
Guo Jun Zhang ◽  
Tatsuki Ohji ◽  
Shuzo Kanzaki
Keyword(s):  
Boron Nitride ◽  
Hot Pressing ◽  
High Performance ◽  
Hexagonal Boron Nitride ◽  
High Strength ◽  
Reactive Sintering ◽  
Boron Source ◽  
Inorganic Reactions ◽  
Reactive Hot Pressing

Based on the proposed inorganic reactions a series of high performance hexagonal boron nitride-containing composites (BNCC), include SiC-BN, Si3N4-SiC-BN, SiAlON-BN, AlN-BN, Al2O3-BN, AlON-BN and mullite-BN, have been prepared via reactive hot pressing or pressureless reactive sintering. Various boron-bearing components such as B, B4C, AlB2, SiB4, SiB6, B2O3 or H3BO3, 9Al2O3×2B2O3 (9A2B) and 2Al2O3×B2O3 (2AB) are used as the boron source. On the other hand, nitrogen gas or solid state nitirgen-bearing metal nitrides such as Si3N4 and AlN can be used as the nitrogen source. The in situ synthesized composites demonstrated homogeneous and isotropical microstructures with very fine (nano-sized) BN platelets or their agglomerates distributed in the matrixes. These composites showed high strength, low elasticity and improved strain tolerance. In this article the reaction design, thermodynamics, reaction mechanisms, reactive hot pressing or pressureless reactive sintering, microstructures and mechanical properties will be discussed.

scholarly journals The effect of various Co contents on the microstructure and properties of Ti(C,N)-TiB2-Co cermets prepared in situ via reactive hot pressing

2020 ◽  
Vol 12 (5) ◽  
pp. 168781402092571
Author(s):  
Xianrui Zhao ◽  
Ze Yu ◽  
Dunwen Zuo ◽  
Qintao Li ◽  
Mengxian Zhang ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Relative Density ◽  
Vickers Hardness ◽  
Hot Pressing ◽  
Hardness Test ◽  
Reactive Hot Pressing ◽  
Compacting Pressure ◽  
Vickers Hardness Test ◽  
Scanning Electron

Ti(C,N)-TiB2-Co cermets were in situ synthesized, via reactive hot pressing from the Co-Ti-C-BN system, with a Co content ranging from 6 to 22 wt%. The microstructure, relative density, hardness, and fracture toughness of the sintered compacts was investigated by light microscopy, scanning electron microscopy, ceramic densitometry, and Vickers hardness test. The investigations indicate that during hot pressing (compacting pressure = 30 MPa), when the Co content is 14–22 wt%, the metal binder is extruded. Co and Ti are included in the extrudate, breaking the original ratio and deteriorating the properties of the sintered products. As the Co content increases from 6 wt% to 12 wt%, the porosity increases, and the relative density increases from 97.2% to 99.5%. The fracture toughness increases from 6.1 to 6.8 MPa m1/2. The Vickers hardness first increases from 1897 HV10 to the maximum 1960 HV10 and then decreases slightly to 1945 HV10.

A study on in-situ synthesis of TiB2–SiC ceramic composites by reactive hot pressing

2014 ◽  
Vol 40 (1) ◽  
pp. 2305-2313 ◽  
Author(s):  
Guolong Zhao ◽  
Chuanzhen Huang ◽  
Hanlian Liu ◽  
Bin Zou ◽  
Hongtao Zhu ◽  
...  
Keyword(s):  
Hot Pressing ◽  
Ceramic Composites ◽  
In Situ Synthesis ◽  
Sic Ceramic ◽  
Reactive Hot Pressing

Ti/B4C Composites Prepared by In Situ Reaction Using Inductive Hot Pressing

2017 ◽  
Vol 742 ◽  
pp. 121-128 ◽  
Author(s):  
Enrique Ariza Galván ◽  
Isabel Montealegre-Meléndez ◽  
Cristina Arévalo ◽  
Michael Kitzmantel ◽  
Erich Neubauer
Keyword(s):  
Mechanical Properties ◽  
Hot Pressing ◽  
Manufacturing Process ◽  
Processing Conditions ◽  
Microstructure And Properties ◽  
Microstructure Observation ◽  
Suitable Processing

In the present work, in situ reinforced titanium composites (TMCs) synthesized using inductive hot pressing (iHP) are studied. The effects of B4C phases and applied processing conditions, on the microstructure and properties of TMCs, are investigated. With the addition of B4C particles, the microstructure of TMCs is refined and the strength is improved.Products of reactions which occur during the manufacturing process are analysed in detail. Microstructure observation illustrates, that B4C survives - depending on the processing conditions. The reinforcing phases are homogeneously distributed in Ti matrix. Moreover, results of densification, mechanical properties and hardness measurements help to identify the most suitable processing conditions to produce this kind of TMCs.

Microstructure of In Situ Tic-Mo-Ni And Tic-WC-Mo-Ni Cermets Synthesized by Reactive Hot-Pressing Sintering

2011 ◽  
Vol 194-196 ◽  
pp. 1785-1788 ◽  
Author(s):  
Zong De Liu ◽  
Li Ping Zhao ◽  
Yan Rong Bao ◽  
Bin Li
Keyword(s):  
Chemical Reactions ◽  
Hot Pressing ◽  
Phase Structure ◽  
Size Range ◽  
Phase Changes ◽  
Binder Phase ◽  
Hot Pressing Sintering ◽  
Reactive Hot Pressing ◽  
Structure And Microstructure

TiC-Mo-Ni and TiC-WC-Mo-Ni cermet blocks have been obtained in situ by reactive hot pressing sintering. The phase structure and microstructure of the two cermets were compared to investigate the effect of the addition of WC. The results show that the chemical reactions between Ti, Mo and C in TiC-Mo-Ni system are relatively complete. However, there is a small amount of unreacted C powder in TiC-WC-Mo-Ni system, which is associated with the reaction between Ti and WC. The in-situ carbide grains are very fine with the size range of 0.5-2µm. The boundary morphology between the carbide grains and the binder phase changes from an angular shape to an almost rounded shape with the addition of WC.

scholarly journals Microstructural evolution and mechanical properties of in situ nano Ta4HfC5 reinforced SiBCN composite ceramics

2020 ◽  
Vol 9 (6) ◽  
pp. 739-748
Author(s):  
Bingzhu Wang ◽  
Daxin Li ◽  
Zhihua Yang ◽  
Dechang Jia ◽  
Jingyi Guan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Microstructural Evolution ◽  
Hot Pressing ◽  
Raw Materials ◽  
Hybrid Structure ◽  
Second Step ◽  
Composite Ceramics ◽  
Hot Pressing Sintering ◽  
Reactive Hot Pressing

AbstractThe in situ nano Ta4HfC5 reinforced SiBCN-Ta4HfC5 composite ceramics were prepared by a combination of two-step mechanical alloying and reactive hot-pressing sintering. The microstructural evolution and mechanical properties of the resulting SiBCN-Ta4HfC5 were studied. After the first-step milling of 30 h, the raw materials of TaC and HfC underwent crushing, cold sintering, and short-range interdiffusion to finally obtain the high pure nano Ta4HfC5. A hybrid structure of amorphous SiBCN and nano Ta4HfC5 was obtained by adopting a second-step ball-milling. After reactive hot-pressing sintering, amorphous SiBCN has crystallized to 3C-SiC, 6H-SiC, and turbostratic BN(C) phases and Ta4HfC5 retained the form of the nanostructure. With the in situ generations of 2.5 wt% Ta4HfC5, Ta4HfC5 is preferentially distributed within the turbostratic BN(C); however, as Ta4HfC5 content further raised to 10 wt%, it mainly distributed in the grain-boundary of BN(C) and SiC. The introduction of Ta4HfC5 nanocrystals can effectively improve the flexural strength and fracture toughness of SiBCN ceramics, reaching to 344.1 MPa and 4.52 MPa·m1/2, respectively. This work has solved the problems of uneven distribution of ultra-high temperature phases in the ceramic matrix, which is beneficial to the real applications of SiBCN ceramics.

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