The process of laser cladding procedure has a closely relation with properties of composite cladding layers. When the input power of laser is certain, the low scanning velocity makes substrate with ahead of laser beam...The process of laser cladding procedure has a closely relation with properties of composite cladding layers. When the input power of laser is certain, the low scanning velocity makes substrate with ahead of laser beam heat for a long time, which worsens interface bonding from surface oxidized; much higher scanning velocity makes the powder’s synthesis near substrate uncompleted fully, the remained powder in interface worsens interface bonding as well. Otherwise, the input specific energy of laser influences on in-situ synthesis courses. If the input energy is lower, the synthesis is not completed fully. In addition, the low temperature effects not only restrict the dispersion of particle leading uneven distribution of TiC, but also form some regions consisting of Al and Al 3Ti.展开更多
The aluminum alloy structure impact localization system by using fiber Bragg grating (FBG) sensors and impact localization algorithm was investigated. A four-FBG sensing network was established. And the power intens...The aluminum alloy structure impact localization system by using fiber Bragg grating (FBG) sensors and impact localization algorithm was investigated. A four-FBG sensing network was established. And the power intensity demodulation method was initialized employing the narrow-band tunable laser. The wavelet transform was used to weaken the impact signal noise. And the impact signal time difference was extracted to build the time difference localization algorithm. At last, a fiber Bragg grating impact localization system was established and experimentally verified. The experimental results showed that in the aluminum alloy plate with the 500mm*500mm*2mm test area, the maximum and average impact abscissa localization errors were 11 mm and 6.25mm, and the maximum and average impact ordinate localization errors were 9 mm and 4.25 mm, respectively. The fiber Bragg grating sensors and demodulation system are feasible to realize the aviation aluminum alloy material structure impact localization. The research results provide a reliable method for the aluminum alloy material structure impact localization.展开更多
基金National Natural Science Foundation ofChina (No.5 98710 3 8)
文摘The process of laser cladding procedure has a closely relation with properties of composite cladding layers. When the input power of laser is certain, the low scanning velocity makes substrate with ahead of laser beam heat for a long time, which worsens interface bonding from surface oxidized; much higher scanning velocity makes the powder’s synthesis near substrate uncompleted fully, the remained powder in interface worsens interface bonding as well. Otherwise, the input specific energy of laser influences on in-situ synthesis courses. If the input energy is lower, the synthesis is not completed fully. In addition, the low temperature effects not only restrict the dispersion of particle leading uneven distribution of TiC, but also form some regions consisting of Al and Al 3Ti.
文摘The aluminum alloy structure impact localization system by using fiber Bragg grating (FBG) sensors and impact localization algorithm was investigated. A four-FBG sensing network was established. And the power intensity demodulation method was initialized employing the narrow-band tunable laser. The wavelet transform was used to weaken the impact signal noise. And the impact signal time difference was extracted to build the time difference localization algorithm. At last, a fiber Bragg grating impact localization system was established and experimentally verified. The experimental results showed that in the aluminum alloy plate with the 500mm*500mm*2mm test area, the maximum and average impact abscissa localization errors were 11 mm and 6.25mm, and the maximum and average impact ordinate localization errors were 9 mm and 4.25 mm, respectively. The fiber Bragg grating sensors and demodulation system are feasible to realize the aviation aluminum alloy material structure impact localization. The research results provide a reliable method for the aluminum alloy material structure impact localization.