scholarly journals In-situ Synthesis and Characterization of Ceramic Reinforced Inconel 718 Coatings Using B4C-Inconel 718 Powders by Laser Directed Laser Energy Deposition

Author(s):  
Yunze Li ◽  
Dongzhe Zhang ◽  
Bo Zhao ◽  
Weilong Cong

Abstract Inconel 718 has been widely used in aerospace, nuclear and marine industries due to excellent high-temperature mechanical properties and corrosion resistance. In recent years, laser directed energy deposition (DED) become a competitive method in the fabrication of Inconel 718 coatings. Compared with other surface coating processes, laser DED has the advantage of extremely fine-grained structures, strong metallurgical bonding, and high density. However, the hardness and wear resistance of Inconel 718 coatings still need to be improved. To further improve these properties, ceramic reinforced Inconel 718 coatings have been investigated. Compared with ex-situ ceramic reinforcements, the in-situ synthesized reinforcements have the advantage of refined ceramic particle size, uniform distribution, and low thermal stress. B4C was a preferable additive material to fabricate in-situ synthesized multi-component ceramic reinforced Inconel 718 coatings. The addition of B4C could form a large number of borides and carbides as ceramic reinforcements. In addition, the in-situ reactions between Inconel 718 and B4C could release heat during the fabrication, thereby promoting the melting of material powders. However, there are currently no investigations on the in-situ synthesis mechanisms, microstructure, and mechanical properties of laser DED fabricated B4C-Inconel 718 coatings. In this study, the effects of B4C on the properties of Inconel 718 coatings were investigated. Results show that Ni3B, NbB, and Cr3C2 phases were formed. With the addition of B4C, the size of Laves phase was refined and the porosity was decreased. The hardness and wear resistance of B4C reinforced coatings were improved by about 34% and 28%, respectively.

Metals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1121 ◽  
Author(s):  
Li ◽  
Liang ◽  
Tian ◽  
Yang ◽  
Xie ◽  
...  

Titanium composite strengthened by Ti3Al precipitations is considered to be one of the excellent materials that is widely used in engineering. In this work, we prepared a kind of Ti-Ti3Al metallic composite by in-situ synthesis technology during the SLM (selective laser melting) process, and analyzed its microstructure, wear resistance, microhardness, and compression properties. The results showed that the Ti-Ti3Al composite, prepared by in-situ synthesis technology based on SLM, had more homogeneous Ti3Al-enhanced phase dispersion strengthening structure. The grain size of the workpiece was about 1 μm, and that of the Ti3Al particle was about 200 nm. Granular Ti3Al was precipitated after the aluminum-containing workpiece formed, with a relatively uniform distribution. Regarding the mechanical properties, the hardness (539 HV) and the wear resistance were significantly improved when compared with the Cp-Ti workpiece. The compressive strength of the workpiece increased from 886.32 MPa to 1568 MPa, and the tensile strength of the workpiece increased from 531 MPa to 567 MPa after adding aluminum. In the future, the combination of in-situ synthesis technology and SLM technology can be used to flexibly adjust the properties of Ti-based materials.


2006 ◽  
Vol 23 (1) ◽  
pp. 29-37 ◽  
Author(s):  
G.D. Janaki Ram ◽  
A. Venugopal Reddy ◽  
K. Prasad Rao ◽  
G. Madhusudhan Reddy

2018 ◽  
Vol 5 (4) ◽  
pp. 171775 ◽  
Author(s):  
Hao Liu ◽  
Jianzhang Wang ◽  
Pengfei Jiang ◽  
Fengyuan Yan

The performance of polymer composites in seawater, under high hydrostatic pressure (typically few tens of MPa), for simulating exposures at great depths in seas and oceans, has been little studied. In this paper, polyetheretherketone (PEEK) and its composites reinforced by carbon fibres and glass fibres were prepared. The seawater environment with different seawater hydrostatic pressure ranging from normal pressure to 40 MPa was simulated with special equipment, in which the seawater absorption and wear behaviour of PEEK and PEEK-based composites were examined in situ . The effects of seawater hydrostatic pressure on the mechanical properties, wear resistance and microstructure of PEEK and its composites were focused on. The results showed that seawater absorption of PEEK and its composites were greatly accelerated by increased hydrostatic pressure in the deep sea. Affected by seawater absorption, both for neat PEEK and composites, the degradation on mechanical properties, wear resistance and crystallinity were induced, the degree of which was increasingly serious with the increase of hydrostatic pressure of seawater environment. There existed a good correlation in an identical form of exponential function between the wear rate and the seawater hydrostatic pressure. Moreover, the corresponding mechanisms of the effects of deep-sea hydrostatic pressure were also discussed.


2021 ◽  
Vol 118 (6) ◽  
pp. 606
Author(s):  
Nandish Girishbhai Soni ◽  
Akash Ganesh Mahajan ◽  
Kaustubh Ramesh Kambale ◽  
Sandeep Prabhakar Butee

Fabrication with the in-situ formation of W2C reinforced medium carbon steel (MCS) MMC’s was attempted using W or WO3 and graphite addition to steel. The P/M route comprising milling, compaction and sintering at 1050 °C and 1120 °C respectively in 90% N2 + 10% H2 atmosphere was adopted. Both SEM and BET studies revealed the particle size to be around 100, 7 and 40 µm for MCS, W and WO3, respectively. A complete conversion of tungsten into tungsten semicarbide (W2C) was noted in XRD for the tungsten additions of ∼6, 9 and 12 wt.% with stoichiometrically balanced C (graphite) addition of 0, 0.2 and 0.4 wt.%. However, WO3 + C addition (balanced as above) revealed the partial conversion of WO3 to W2C. The peaks of Fe3C were observed only for MCS + W + C samples and not for MCS + WO3 + C samples in XRD. In SEM, the WO3 phase appeared porous and partially converted, whereas, W2C phase was dense. Sintered density improved for the addition of W, whereas it monotonically reduced for WO3 addition to MCS + C samples. Higher hardness, compressive strength, and wear resistance was noted for W addition than WO3 to MCS+C samples.


2021 ◽  
Vol 197 ◽  
pp. 109214
Author(s):  
Xiaoqiang Zhang ◽  
Ze Chai ◽  
Huabin Chen ◽  
Jijin Xu ◽  
Luming Xu ◽  
...  

2015 ◽  
Vol 18 (4) ◽  
pp. 550-558 ◽  
Author(s):  
Riccardo Casati ◽  
Alberto Fabrizi ◽  
Giulio Timelli ◽  
Ausonio Tuissi ◽  
Maurizio Vedani

2015 ◽  
Vol 3 (15) ◽  
pp. 8205-8214 ◽  
Author(s):  
Jia Wei ◽  
Shuo Zhang ◽  
Xiaoyun Liu ◽  
Jun Qian ◽  
Jiasong Hua ◽  
...  

BaTiO3/MWNT/PBO ternary composites with excellent microwave absorption properties, mechanical properties and thermostabilities.


Sign in / Sign up

Export Citation Format

Share Document