ObjectiveFlash phenomena occur in various impact scenes. By capturing the flash spectra and analyzing their spectral line wavelengths and intensities, many critical pieces of information can be obtained, such as the composition of the colliding materials, the intensity of the radiation, and other environmental conditions. In the field of deep space exploration, obtaining the types of materials such as space meteorites and analyzing their structures are important indicators of deep space exploration missions, and it is of great significance to study the flash spectra generated by the collision of space materials and analyze the time-varying characteristics of the collision spectra for the development of deep space exploration technology.
MethodsThe study investigates the collision spectral properties of a metal alloy consisting of Al and a small amount of W hitting a steel plate by means of a high-speed metallic material collision experiment. The experiment was conducted by laser targeting to focus the telescopic fiber-coupled lens on the surface of the steel plate and to collect the collision spectra within a spatial radius of 0.3 m, as shown in Fig.2. The flight speed of metal materials is measured by broken-target velocimeter. The experiment sets the integration time of the spectrometer to 50 μs and collects it continuously for 10 times, in order to ensure that the integration time can contain the moment of impact flash, the delayed triggering function of the broken-target velocimeter is used to realize the delayed triggering of the spectrometer.
Results and DiscussionsFigure 3 shows that at the beginning of the collision, the collision core area has the strongest brightness, and then high-temperature thermal radiation occurs and rapidly spreads to the entire target surface. From the high-speed photographic data and spectral data, it can be inferred that at the moment of the first effective spectral acquisition, the metal material begins to collide with the steel plate and disintegrate, and the temperature begins to gradually increase, and at this time, the main collection of the material is the impurity composition of the most easy to be excited by the spectral lines of Na I and K I. At the moment of the second acquisition, the metallic material starts to melt under the high temperature, and oxidizes with O
2 and CO
2 in the air under the high temperature condition, while the small amount of W in the metallic material starts to be excited to produce spectral lines. As the collision progresses, the burning of Al particles is limited by the surface oxidation rate, and the AlO emission lines disappear while the intensity of other lines decreases.
ConclusionsFrom the effective spectral data, it is easy to find that the intensity of the line spectra formed by atoms (Ions) is much higher than that of the continuous spectrum formed by high-temperature thermal radiation, and that the line spectra mainly come from Na and K, as well as Al and W in metallic materials, with the Na and K spectral lines being present in almost the entire collision process. With the collision process of metal materials, more and more line spectra were excited in the second acquisition, and several line spectra appeared in the range of 460-530 nm, which were mainly the emission spectra of AlO generated by the combustion of Al gas phase, and the high-speed photographic data could see that the metal materials were completely broken at this time and impacted the steel plate, which can be proposed that the collision of aluminum alloys and steels as the main materials could be based on whether the collision was sufficient or not. It can be suggested that in the collision of aluminum alloy and steel as the main materials, the spectral lines within the range of 460-530 nm can be used as the basis for whether the collision is sufficient or not.