We investigate a novel and compact fiber-tip pressure sensor based on Fabry-Perot interferometer (FPI). The proposed device is fabricated by welding a Section of hollow silica tube (HST) on the end of single mode fiber (SMF) and then coating with ultraviolet (UV) curable polymer film at the tip of HST. A simple suspension curing method is introduced to control the formation of the UV curable polymer layer. Therefore, different thicknesses of the polymer film can be easily controlled. The pressure sensing mechanism is based on the cavity length change induced by ambient pressure. The sensor characteristics are studied theoretically and experimentally. The proposed fiber-tip pressure sensor with polymer film thickness of $5.7\,\, \mu \text{m}$ exhibits a pressure sensitivity of 396 pm/kPa in the range of 0–30 kPa based on wavelength shift of the interference dip. Moreover, temperature crosstalk is measured, and the thermal-induced deformation of the polymer film is simulated using the Finite Element Analysis method. The proposed fiber-tip Fabry-Perot cavity pressure sensor has advantages of high sensitivity, fast response, excellent repeatability, compact size, cost effectiveness and easy fabrication, which makes it suitable for high sensitivity pressure detection in a limited space.

Optical fiber Fabry–Perot sensors have long been the focus of researchers in sensing applications because of their unique advantages, including highly effective, simple light path, low cost, compact size, and easy fabrication. Microcantilever-based devices have been extensively explored in chemical and biological fields while the interrogation methods are still a challenge. The optical fiber probe microcantilever sensor is constructed with a microcantilever beam on an optical fiber, which opens the door for highly sensitive, as well as convenient readout. In this review, we summarize a wide variety of optical fiber probe microcantilever sensors based on Fabry–Perot interferometer. The operation principle of the optical fiber probe microcantilever sensor is introduced. The fabrication methods, materials, and sensing applications of an optical fiber probe microcantilever sensor with different structures are discussed in detail. The performances of different kinds of fiber probe microcantilever sensors are compared. We also prospect the possible development direction of optical fiber microcantilever sensors.

To increase the surface quality of the high-strength maraging steel metal materials, a new method of executing the additive manufacturing process and subtraction polishing process of maraging steel metal materials was studied. The mechanical properties of maraging steel metal materials before and after laser powder bed fusion (LPBF) polishing were compared and analyzed. The influence of laser parameters on the formability of high-strength MS metal materials was studied, with MS additive parts successfully prepared. The initial surfaces had roughness values of 6.198–7.92 μm. The metal additive manufacturing parts were polished with double laser beams. Confocal microscopy, scanning electron microscopy, and X-ray diffraction were used to obtain the microstructure and phase composition of the microstructures. The microhardness of high-strength maraging forming parts by using a microhardness tester and the mechanical properties were analyzed. The results showed that the surface roughness was considerably reduced to lengthen the service life of the high-strength MS metal materials from an initial roughness of Sa = 6.3 μm to Sa = 0.98 μm, with the surface hardness increased and the martensite content decreased after using double-laser-beam polishing.