The effect of plasma arc powder surfacing process on the amount of B4C particles in the coating and the thermal behavior of B4C particles in different surfacing stages has been investigated.The results showed that the...The effect of plasma arc powder surfacing process on the amount of B4C particles in the coating and the thermal behavior of B4C particles in different surfacing stages has been investigated.The results showed that the feeding rate of B4C partiles is the most important factor affecting the amount of B4C particles in the surfacing coating among all the surfacing parameters,and the most part of B4C Particles in the coating is nto the remainders of original solid B4C particles,but the consolidation products of the unmelted liquid B4C globules in the pool.The results also showed that the B4C particles would not be melted in the plasma arc column, their melting process mainly takes place in the anode spot region on the surface of the pool when surfacing current is less than 200A.展开更多
In this paper, the influence of plasma arc powder surfacing technical parameters on the property of layer is defined using the orthogonal design. By the orthogonal polynomial regression, when plasma arc powder surfaci...In this paper, the influence of plasma arc powder surfacing technical parameters on the property of layer is defined using the orthogonal design. By the orthogonal polynomial regression, when plasma arc powder surfacing is used on the surface of the X65 steel plate with the Fe-07 alloy powder, the optimum technical parameters are the following: I=180～190 A , G=41.5 g/min , v=102 mm/min , T_0=350 ℃ , Q_l=280 L/h , Q_s=400 L/h . Further, analysis of the cracking test data showed that the cracking preheat temperature is 350 ℃ .展开更多
In order to solve the problem of single arc plasma actuator's failure to suppress the boundary layer separation, the effectiveness of the array surface arc plasma actuator to enhance the excitation intensity is ve...In order to solve the problem of single arc plasma actuator's failure to suppress the boundary layer separation, the effectiveness of the array surface arc plasma actuator to enhance the excitation intensity is verified by experiment. In this study, an electrical parameter measurement system and high-speed schlieren technology were adopted to delve into the electrical, flow field, and excitation characteristics of the high-energy array surface arc plasma actuator under low ambient pressure. The high-energy array surface arc discharge released considerable heat rapidly;as a result, two characteristic structures were generated, i.e., the precursor shock wave and thermal deposition area. The duration increased with the increase in environmental pressure. The lower the pressure, the wider the thermal deposition area's influence range. The precursor shock wave exhibited a higher propagation speed at the initial phase of discharge;it tended to decay over time and finally remained at 340 m/s. The lower the environmental pressure, the higher the speed would be at the initial phase. High-energy array surface arc plasma actuator can be employed to achieve effective high-speed aircraft flow control.展开更多
文摘The effect of plasma arc powder surfacing process on the amount of B4C particles in the coating and the thermal behavior of B4C particles in different surfacing stages has been investigated.The results showed that the feeding rate of B4C partiles is the most important factor affecting the amount of B4C particles in the surfacing coating among all the surfacing parameters,and the most part of B4C Particles in the coating is nto the remainders of original solid B4C particles,but the consolidation products of the unmelted liquid B4C globules in the pool.The results also showed that the B4C particles would not be melted in the plasma arc column, their melting process mainly takes place in the anode spot region on the surface of the pool when surfacing current is less than 200A.
文摘In this paper, the influence of plasma arc powder surfacing technical parameters on the property of layer is defined using the orthogonal design. By the orthogonal polynomial regression, when plasma arc powder surfacing is used on the surface of the X65 steel plate with the Fe-07 alloy powder, the optimum technical parameters are the following: I=180～190 A , G=41.5 g/min , v=102 mm/min , T_0=350 ℃ , Q_l=280 L/h , Q_s=400 L/h . Further, analysis of the cracking test data showed that the cracking preheat temperature is 350 ℃ .
文摘In order to solve the problem of single arc plasma actuator's failure to suppress the boundary layer separation, the effectiveness of the array surface arc plasma actuator to enhance the excitation intensity is verified by experiment. In this study, an electrical parameter measurement system and high-speed schlieren technology were adopted to delve into the electrical, flow field, and excitation characteristics of the high-energy array surface arc plasma actuator under low ambient pressure. The high-energy array surface arc discharge released considerable heat rapidly;as a result, two characteristic structures were generated, i.e., the precursor shock wave and thermal deposition area. The duration increased with the increase in environmental pressure. The lower the pressure, the wider the thermal deposition area's influence range. The precursor shock wave exhibited a higher propagation speed at the initial phase of discharge;it tended to decay over time and finally remained at 340 m/s. The lower the environmental pressure, the higher the speed would be at the initial phase. High-energy array surface arc plasma actuator can be employed to achieve effective high-speed aircraft flow control.
