Development of a portable laser peening device and its effect on the fatigue properties of HT780 butt-welded joints

Sano, Yuji; Kato, Tomoharu; Mizuta, Yoshio; Tamaki, Satoshi; Yokofujita, Koki; Taira, Takunori; Hosokai, Tomonao; Sakino, Yoshihiro

doi:10.1016/j.finmec.2022.100080

Cited by 14 publications

(8 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 2 shows the configuration of the portable LP device using a thumb-sized Nd:YAG microchip laser mounted on a 6-axis collaborative robot arm 6) . The system comprises the robot arm with the microchip laser, a power supply and water circulation system, and a control PC.…”

Section: Portable Lp Devicementioning

confidence: 99%

Effect of Laser Peening on Fatigue Properties of Butt-Welded Joints with Angular Distortion

Kato,

Sakino,

Sano

et al. 2023

QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY

Self Cite

View full text Add to dashboard Cite

Laser peening (LP) is a well-established technique for introducing compressive residual stress (RS) near the surface of metal components to improve their high-cycle fatigue properties. In this study, butt-welded joint specimens of SBHS500 steel with angular distortion were prepared and treated with LP. X-ray diffraction showed that the maximum compressive RS over 400 MPa was introduced near the surface by applying LP with an irradiated pulse energy of 7.5 mJ, a spot size of 0.42 mm, and a pulse density of 800 pulses/mm 2 . The effect reached a depth of approximately 0.15 mm from the surface. The specimens were subjected to a uniaxial fatigue test with a stress ratio of 0.1 together with specimens without LP. The results showed that the fatigue life was prolonged by LP. However, in the stress range of 300 MPa, the detrimental effect of angular distortion predominates over the beneficial effect of LP, showing that the fatigue life extension by LP is not evident.

show abstract

Section: Portable Lp Devicementioning

confidence: 99%

Effect of Laser Peening on Fatigue Properties of Butt-Welded Joints with Angular Distortion

Kato,

Sakino,

Sano

et al. 2023

QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY

Self Cite

View full text Add to dashboard Cite

show abstract

“…Unfortunately, it takes time to improve the fatigue strength by laser cavitation peening as the repetition frequency of the pulsed laser is about several dozen times per second. Although a high-repetition portable pulse laser, whose power and pulse width are 10 mJ and 1.3 ns, was developed in [52], its repetition frequency was only about 100 Hz, and 800-1600 pulses/mm 2 were required for treatment. Even then, it still requires a long time to treat the target.…”

Section: Introductionmentioning

confidence: 99%

Development of a Cavitation Generator Mimicking Pistol Shrimp

Soyama,

Tanaka,

Takiguchi

et al. 2024

Biomimetics

View full text Add to dashboard Cite

Pistol shrimp generate cavitation bubbles. Cavitation impacts due to bubble collapses are harmful phenomena, as they cause severe damage to hydraulic machinery such as pumps and valves. However, cavitation impacts can be utilized for mechanical surface treatment to improve the fatigue strength of metallic materials, which is called “cavitation peening”. Through conventional cavitation peening, cavitation is generated by a submerged water jet, i.e., a cavitating jet or a pulsed laser. The fatigue strength of magnesium alloy when treated by the pulsed laser is larger than that of the jet. In order to drastically increase the processing efficiency of cavitation peening, the mechanism of pistol shrimp (specifically when used to create a cavitation bubble), i.e., Alpheus randalli, was quantitatively investigated. It was found that a pulsed water jet generates a cavitation bubble when a shrimp snaps its claws. Furthermore, two types of cavitation generators were developed, namely, one that uses a pulsed laser and one that uses a piezo actuator, and this was achieved by mimicking a pistol shrimp. The generation of cavitation bubbles was demonstrated by using both types of cavitation generators: the pulsed laser and the piezo actuator.

show abstract

“…In general, laser-based processing is noncontact, clean, and high-speed, which can be feasibly integrated on robot and computer numerical control (CNC) platforms with increased functions, accuracy, and efficiency [21]. Along with the rapid developments of semiconductor technologies in the past decades [22][23][24], microchip lasers have now been entering surface enhancement applications for metal alloys, including LSP, texturing, welding, etc [25][26][27][28]. Driven by advanced additive manufacturing in recent years, integration of laser processes has been proposed for innovative manufacturing and/or remanufacturing [29][30][31].…”

Section: Introductionmentioning

confidence: 99%

Laser-treatment-induced surface integrity modifications of stainless steel

Gong

Wei

Meng

et al. 2023

Mater. Res. Express

View full text Add to dashboard Cite

Scanning of high-power laser beam on surface of martensitic stainless steel (SS420) has been studied, addressing the effect of scanning rate V on integrity modifications in the near-surface regions. Structural, compositional, and crystallographic characterizations revealed the presence of ablations, surface melting/resolidification, surface oxidations, and austenite (γ-phase) precipitations when V ≤ 20 mm/s. Melt pool (MP), heat affected zone (HEA), and base material have been clearly distinguished at the cross-section of the slow-scanned samples. Adjacent MPs partially overlapped when V = 5 mm/s. The γ-phase precipitations solely occurred in the MPs, i.e., of ~ 400 μm deep for V = 5 mm/s, while oxidations dominantly occurred in the surface regions of shallower than ~30 μm within the MPs. Compositional analysis revealed increased Cr-, Mn-, and Si-to-Fe ratios at the laser-scanned surface but absence of variations along the surface normal direction. Hardened surface has been achieved up to 805 HV, and the hardening monotonically decreased when moving deeper (i.e., ~1000 μm) into the base material. These observations shed new lights on surface engineering of metallic alloys via laser-based direct energy treatments.

show abstract

Development of a portable laser peening device and its effect on the fatigue properties of HT780 butt-welded joints

Cited by 14 publications

References 24 publications

Effect of Laser Peening on Fatigue Properties of Butt-Welded Joints with Angular Distortion

Effect of Laser Peening on Fatigue Properties of Butt-Welded Joints with Angular Distortion

Development of a Cavitation Generator Mimicking Pistol Shrimp

Laser-treatment-induced surface integrity modifications of stainless steel

Contact Info

Product

Resources

About