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In this work, the antiscaling and antiwaxing properties are evaluated by surface roughness testing, water contact angle measurements, scale and wax deposition testing, and potentiodynamic polarization analysis, respectively. The morphologies and microstructures of the samples before and after ultrasonic surface rolling process (USRP) are analyzed by scanning electron microscopy and optical microscopy, respectively. The results show that for 316L stainless steel after USRP, its surface roughness and surface energy decrease by 97% and 27%, respectively, and the average scale amount is decreased by 73% and antiwaxing rate is up to 63%. In contrast, for the A3 steel after USRP, the average amount of scale and wax deposition increases due to the enhanced atomic activity of the surface layer and surface energy although its reduced surface roughness. It is found that the lower surface energy is the primary factor for improving the antiscaling and antiwaxing performance. A second factor may be related to the smooth surface and superior corrosion resistance.

The efficient upconversion (UC) particles based on fluorescence intensity ratio (FIR) technique are developed for application in novel temperature sensors. Herein, Yb3+/Er3+‐codoped Gd2(WO4)3 particles are prepared by coprecipitation method and subsequent calcination. The phase structure and surface morphology of the particles are systematically analyzed. The UC emission spectrum of Gd2(WO4)3:Yb3+/Er3+ particles are mainly composed of two strong emission bands centered at 530 and 551 nm, respectively. Moreover, the optimum doping concentration of Yb3+ and Er3+ is fixed at 10% and 2%, respectively. UC emission mechanism based on two‐photon process is investigated by studying the pump power excitation dependence and fluorescence decay behavior of Gd2(WO4)3:10%Yb3+/2%Er3+ particles. The excellent temperature sensing capability of Gd2(WO4)3:10%Yb3+/2%Er3+ particles is implemented from thermally coupled levels (TCLs) of Er3+. Notably, the maximum absolute sensitivity (S a) and relative sensitivity (S r) based on TCLs by 2H11/2/4S3/2 levels are 1.39 %K−1 (at 518 K) and 1.18 %K−1 (at 293 K), respectively. As a result, Gd2(WO4)3:10%Yb3+/2%Er3+ particles have a great potential for application in noncontact temperature sensors.

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