Investigations on TC4-DT titanium alloy using laser shock processing with high energy

2012 ◽  
Vol 10 (s2) ◽  
pp. S21408-321410 ◽  
Author(s):  
Zhigang Che Zhigang Che ◽  
Jianhui Dai Jianhui Dai ◽  
Haiying Xu Haiying Xu ◽  
Shikun Zou Shikun Zou ◽  
Ziwen Cao Ziwen Cao
Keyword(s):  
Titanium Alloy ◽  
High Energy ◽  
Laser Shock ◽  
Laser Shock Processing ◽  
Shock Processing

High Dense Compressive Residual Stress Produced in Laser Shock Processing on Ti6Al4V Alloys

2007 ◽  
Vol 353-358 ◽  
pp. 1617-1620 ◽  
Author(s):  
Xu Dong Ren ◽  
Yong Kang Zhang ◽  
Jian Zhong Zhou ◽  
Yong Yu Gu ◽  
Y.Y. Xu ◽  
...  
Keyword(s):  
Residual Stress ◽  
Fatigue Crack ◽  
Surface Stress ◽  
Compressive Residual Stress ◽  
High Energy ◽  
Laser Shock ◽  
Laser Shock Processing ◽  
Large Spot ◽  
Small Spot ◽  
Shock Processing

Laser shock processing (LSP) employs high-energy laser pulses from a solid-state laser system to create intense shock waves into a material, which can induce compressive residual stresses in the target surface and improve its mechanical property efficiency. Residual stress of Ti6Al4V alloy both before and after LSP with multishocks was analysised. The depth of compressive residual stress was found to have a dependence on the number of shocking layers and a slight dependence on the level of irradiance. Surface stress improvements of more than 50% increases are possible after laser shock processing with either large spot or small spot patterns. The large spot gave a surface stress of 432MPa and a depth of over 1mm. The low intensity small spot gave a surface stress of 285MPa with a depth comparable to the large spot. Laser shock processing induces a compressive residual stress field, which increases fatigue crack initiation life and reduces fatigue crack growth rate.

The Fracture Microphology of the Ceramics by Strong Laser Shock Processing

2006 ◽  
Vol 532-533 ◽  
pp. 137-140 ◽  
Author(s):  
Ling Feng Zhang ◽  
Yong Kang Zhang ◽  
Ai Xin Feng
Keyword(s):  
Plastic Deformation ◽  
Brittle Fracture ◽  
Radial Crack ◽  
Laser Energy ◽  
High Energy ◽  
Laser Shock ◽  
Main Mode ◽  
Laser Shock Processing ◽  
Strong Laser ◽  
Shock Processing

The laser shocking to the Al2O3 ceramics was proceeded, and the fracture microphology that formed from the strong laser shock processing (LSP) was analyzed by the Scanning electron microscopy (SEM). It was discovered that the feature of ceramics responds differently when the laser energy was changed. The brittle fracture that consists of intergranular fracture and cleavage fracture was the main mode under high energy laser shocking (laser pulse enegry: 42J); the macroscopical fracture characteristic was the radial crack. When the laser energy reduced to a fit level (25J), the brittle fracture of ceramics appears to the characteristic of plastic deformation, its fracture microphology appears lots of slippage lines, and the macroscopical feature of radial crack under 42J become subulate crack. While the energy reduced to 15J, the Al2O3 ceramics did not fracture, its micro-hardness ascended, a feature of micro-plastic deformation was existed under the low energy. The reason of the brittle materials appears to the feature of plastic deformation was analyzed.

Laser Shock Processing of Titanium Alloy Blade and FEM Simulation

2013 ◽  
Vol 456 ◽  
pp. 125-128
Author(s):  
Bing Yan ◽  
Rui Wang
Keyword(s):  
Residual Stress ◽  
Titanium Alloy ◽  
Residual Stresses ◽  
Fem Simulation ◽  
Laser Shock ◽  
Laser Shock Processing ◽  
Tc4 Titanium Alloy ◽  
Compressive Stresses ◽  
Maximum Value ◽  
Shock Processing

The aim of this article is to analyze the residual stresses field in a TC4 titanium alloy blade by laser shock processing (LSP).LSP is a new surface processing technology, it uses the laser shock wave to act on the surface of the target and form residual compressive stresses field. The ABAQUS software is applied to simulate the LSP of TC4 titanium alloy blade, and the distributions of the residual stresses field are analysed.After single LSP,the maximum value of residual stress on the surface is 309 MPa.The residual stresses on the surface increase first and then decrease.The residual stresses at the depth continue decreasing with the increase of the depth.After multiple LSP,the maximum value of residual stress on the surface is increased and plastically affected depth is increased.

Experiment of Laser Shock Processing on AISI 8620 Alloy Steel

2011 ◽  
Vol 464 ◽  
pp. 478-481
Author(s):  
R.H. Shen ◽  
J.Z. Lu ◽  
J.W. Zhong ◽  
L. Zhang ◽  
Kai Yu Luo ◽  
...  
Keyword(s):  
Residual Stress ◽  
Surface Hardness ◽  
Base Material ◽  
High Amplitude ◽  
High Energy ◽  
Laser Shock ◽  
Laser Shock Processing ◽  
Before And After ◽  
Shock Peening ◽  
Shock Processing

Laser shock processing (LSP, also known as Laser shock peening) is applied by using a high energy pulsed laser to create a high amplitude stress wave or shock wave on the surface to be treated. LSP is proved to be superior to conventional treatments such as shot peening in many engineering products. This paper focuses on Laser shock processing and its effects on mechanical properties of material AISI 8620 alloys steel. Experiment results indicated that compared with base material, the surface hardness increased by 13.8%, and compressive residual stress increased by 521%. Statistical method was introduced to analyze hardness and residual stress change before and after the LSP.

Thermostablity Study on Microstructure and Microhardness of Laser Shock Processed Ti-6Al-2.5Mo-1.5Cr-0.5Fe-0.3Si

2011 ◽  
Vol 697-698 ◽  
pp. 440-444 ◽  
Author(s):  
Qi Peng Li ◽  
Ying Hong Li ◽  
W. He ◽  
Yu Qin Li ◽  
Xiang Fan Nie ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Cross Section ◽  
High Strain ◽  
Microscopic Structure ◽  
Laser Shock ◽  
Laser Shock Processing ◽  
Fine Grain ◽  
High Strain Rate Deformation ◽  
The Usa ◽  
Shock Processing

In this paper, the microstructure and microhardness of laser shock processed (LSP) Ti-6Al-2.5Mo-1.5Cr-0.5Fe-0.3Si titanium alloy with and without annealing were examined and compared. The titanium alloy samples were LSP processed with 3 layers at 4.24GW/cm2. Some of the samples were vacuum annealed at 623K for 10 hours. The microscopic structure with and without annealing were tested and analyzed by SEM, TEM. The results indicated that after LSP, the shock wave provided high strain rate deformation and led to the formation of ultra-fine grain. Comparing with the samples without annealing, the dislocation density was lower and the grain-boundary was more distinct in the annealed samples, but the sizes of the ultra-fine grain didn’t grow bigger after annealing. On the other hand, the microhardness measurement was made on the cross-section. It is obviously that the laser shock processing improved the microhardness of the Ti-6Al-2.5Mo-1.5Cr-0.5Fe-0.3Si for about 12.2% at the surface, and the hardness affected depth is about 500 microns. The microhardness after annealing is 10 HV0.5lower, but the affected depth is not changed. The titanium alloy after LSP is thermostable at 623K; thus break the USA standard AMS2546, in which titanium parts after LSP are subjected in subsequent processing should not exceed 589K.

Sign in / Sign up

Export Citation Format

Share Document