scholarly journals Numerical Simulation on Pulsed Laser Ablation of the Single-Crystal Superalloy Considering Material Moving Front and Effect of Comprehensive Heat Dissipation

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 225
Author(s):  
Bin Wang ◽  
Yihui Huang ◽  
Junke Jiao ◽  
Hao Wang ◽  
Ji Wang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Laser Ablation ◽  
Single Crystal ◽  
Heat Dissipation ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Recast Layer ◽  
Single Crystal Superalloy ◽  
Thermal Dissipation ◽  
Moving Front

In the present research, an iterative numerical model is proposed to investigate the nanosecond pulsed laser ablation (PLA) mechanism of the DD6 single-crystal superalloy. In the numerical model, two subroutines are introduced to trace the moving boundary and update the thermal load. The iteration between the main governing equation and the two subroutines enables the PLA numerical simulation to consider material moving front and effect of comprehensive heat dissipation including thermal convection and radiation. The basic experimental results exhibit a good agreement with simulation results which indicates the good accuracy of the simulation model. Therefore, the PLA mechanism of the DD6 single-crystal superalloy is studied base on the improved iterative model, which indicates the evolution of temperature field, ablation zone morphology, formation of recast layer and heat-affected zone are closely related with time. The temperature of the laser spot center increases sharply at the first stage, reaching a maximum value of 5252 K, and then decreases gradually. The thermal dissipation postpones the ablation rate but promotes the formation of a recast layer and heat-affected zone. Due to the evaporation and thermal dissipation, the depth of the molten layer exhibits two rapid increasing stages. The comprehensive analysis of the PLA processing by the improved simulation model helps the understanding of the intrinsic mechanism, which would contribute to the further optimizing parameters of PLA fabrication of the DD6 single-crystal superalloy.

Experiment Study and Numerical Simulation of Pulsed Laser Ablation Crater

2009 ◽  
Vol 36 (1) ◽  
pp. 219-223 ◽  
Author(s):  
刘会霞 Liu Huixia ◽  
杨胜军 Yang Shengjun ◽  
王霄 Wang Xiao ◽  
李黎辉 Li Lihui
Keyword(s):  
Numerical Simulation ◽  
Laser Ablation ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Experiment Study ◽  
Ablation Crater

Formation of Submicron Single Crystal Particles and Dots by Laser Ablation

1994 ◽  
Vol 358 ◽  
Author(s):  
Hong Wu ◽  
R. D. Vispute ◽  
J. Narayan
Keyword(s):  
Quantum Dots ◽  
Laser Ablation ◽  
Single Crystal ◽  
Critical Size ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Liquid Droplets ◽  
Device Applications ◽  
Krf Excimer Laser ◽  
Lattice Matched

ABSTRACTWe have investigated the formation of micron-sized single crystal dots of germanium by pulsed laser ablation. The laser ablation of a Ge target (KrF excimer laser λ=248 nm, pulse rate 10Hz, pulse duration 25x10−9 seconds, and energy 10J /cm2) results in the formation of micron and submicron liquid droplets which are ejected from the target. These droplets can be crystallized into single crystal dots on lattice-matched substrates by rapid liquid-phase recrystallization. We report the details of microstructure as a function of dot size. It is found that under these conditions, below a critical size (about 2μm), the dots are crystalline;above which dots become polycrystalline. We discuss the implications of the results in producing doped and undoped single-crystal quantum dots for device applications.

Study of cobalt oxide films deposited on single-crystal yttria-stabilized zirconia by pulsed-laser ablation

1993 ◽  
Vol 51 ◽  
pp. 1154-1155
Author(s):  
Sundar Ramamurthy ◽  
Stuart McKernan ◽  
C. Barry Carter
Keyword(s):  
Laser Ablation ◽  
Single Crystal ◽  
Cobalt Oxide ◽  
Laser System ◽  
Oxide Films ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Yttria Stabilized Zirconia ◽  
Temperature Phase ◽  
Stabilized Zirconia

One of the most common applications of pulsed-laser ablation (PLA) is the production of oxide films of almost any stoichiometry. In this work, thin films of cobalt oxide were grown onto single-crystal yttria-stabilized zirconia (YSZ) substrates of (100) orientation. Film morphology during the early stages of growth has been studied.Cobalt oxide films grown on suitable substrates have potential applications in electronic and magnetic devices. Like most transition metal oxides, cobalt oxide exists in more than one form, depending on the valence of the cations and their distribution . The transition from CoO to Co3O4 occurs at about 900°C in air, CoO being the high-temperature phase. However, by lowering the partial pressure of oxygen, the CoO stability region shifts down to much lower temperatures.The laser system used for the depositions was a Lambda Physik model 210i with KrF excimer laser (λ=248 nm) operating at an energy of 200 mJ per pulse. A Co3O4 pellet (96% dense) was fabricated as the target material.

Numerical simulation of pulsed laser ablation in air

2003 ◽  
Author(s):  
Bukuk Oh ◽  
Dongsik Kim ◽  
Wonseok Jang ◽  
Bosung Shin
Keyword(s):  
Numerical Simulation ◽  
Laser Ablation ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation
Sign in / Sign up

Export Citation Format

Share Document