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Due to excellent properties, Cr12MoV mold steel, 9Cr18 stainless steel and H13A cemented carbide are widely used in industry. In this paper, the effect of absorption of laser light on ablation efficiency and roughness have been studied using a picosecond pulse Nd:YVO4 laser. The experimental results reveal that laser wavelength, original surface roughness and chemical composition play an important role in controlling ablation efficiency and roughness. Firstly, higher ablation efficiency with lower surface roughness is achieved on the ablation of 9Cr18 at 532, comparing with 1064 nm. Secondly, the ablation efficiency increases while the Ra of the ablated region decreases with the decrease of original surface roughness on ablation of Cr12MoV mold steel at 532 nm. Thirdly, the ablation efficiency of H13A cemented carbide is much higher than 9Cr18 stainless steel and Cr12MoV mold steel at 1064 nm. Scanning electron microscopy images reveals the formation of pores on the surface of 9Cr18 stainless steel and Cr12MoV mold steel at 532 nm while no pores are formed at 1064 nm. As to H13A cemented carbide, worm-like structure is formed at 1064 nm. The synergetic effects of the heat accumulation, plasma shielding and ablation threshold on laser ablation efficiency and machining quality were analyzed and discussed systematically in this paper.

Perovskite solar cells (PSCs) are a promising application industry, but its stability is not very ideal at present. The bottleneck of the PSCs industrialization is that perovskite material is very sensitive to humidity, and it is easy to produce hydrolysis and failure. Therefore, it is necessary to develop an effective encapsulation method to achieve a better long-term stability. Ultrashort pulse laser glass welding technology is one of the effective encapsulation methods, but it is still difficult to be used in engineering due to the harsh conditions of optical contact. To solve these problems, a sealing welding method of perovskite films based on ultrashort pulse laser under the natural stacking conditions was proposed, the effectiveness of the sealing weld was verified by experiments, which provides support for the engineering application of perovskite solar cells, and also provides a possible direction for the application of ultrashort pulse laser glass welding technology.

In this study, long-range ordered straight holes with definable open pattern and diameter of 100–200 μm were manufactured using a 355 nm Nd:YVO 4 ultraviolet laser to sustain Nafion resin for durable proton exchange membranes. Composite proton exchange membrane prepared from the straight-hole polyimide support successfully reduced the dimensional swelling and humidity-induced stress of the proton exchange membrane under variable humidities. The effect of laser fluence and overlap rate on the size precision and quality of the straight holes were investigated. The thermodynamic mechanical capacity of composite proton exchange membrane and the single cell performance were also determined. The experimental results showed that long-range ordered straight holes with high precision and good quality could be achieved by laser trepanning with appropriate scanning speed, high repetition frequency and suitable laser fluence.