Nickel-based superalloys are widely used in aviation, aerospace, energy, petrochemical and other industrial fields due to their excellent high temperature strength, oxidation and corrosion resistance, excellent creep and fatigue resistance. However, there are many problems in the traditional processing methods, such as tool wear, thermal/mechanical damage of materials and so on. These problems limit the processing ability of micro structures and complex surfaces, making it difficult to process nickel-based superalloy components with high quality. Laser processing has the advantages of high precision, non-contact and green, which has become an effective means of nickel-based superalloy surface processing. In this paper, a new process of rotational multi-beam coupled nanosecond laser processing was used to study the groove cutting of nickel-based superalloy with variable defocus amount. The morphology and structure of the groove were observed and analyzed by laser confocal microscope and scanning electron microscope. The results show that the groove width is the smallest and the groove depth is larger when the defocus amount is -1.0mm, and the laser energy density is larger when the defocus amount is close to -1.0mm, and a relatively high adhesion layer is formed between the groove edge and the unmachined surface. By analyzing the groove straightness under different defocus amounts, the groove straightness first decreases and then increases, and the straightness is the smallest at -1.0mm, indicating that -1.0mm defocus position is a relatively suitable processing position. The research work can provide process guidance for the laser processing application of nickel-based superalloys.
SiC ceramics have excellent physical and chemical properties, and have been extensively researched and used in electronics, optics, semiconductor and other fields. However, due to its high strength, high hardness and other characteristics, the conventional processing of SiC ceramics faces a series of challenges. Laser processing has become an effective processing technology due to its unique advantages. In this paper, the single pulse ablation tests of SiC ceramic with different powers were performed by using infrared femtosecond laser. The single pulse ablation threshold of SiC ceramic was calculated by using equivalent diameter method and equivalent area method, and the influence of laser power on the depth of the ablation hole was discussed. The results show that when the repetition frequency is 25kHz and the wavelength is 1035nm, the laser ablation values calculated by the equivalent diameter method and the equivalent area method are 0.3454 J/cm2 and 0.3268 J/cm2, respectively. Within a certain laser power range or reaching a certain ablation hole depth, the ablation hole depth augments with the increment of laser power. Beyond a specified laser power range, the hole depth decreases with the increment of laser power due to the effect of plasma shielding and recasting layer.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.