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In order to replace the hazardous chromate‐based surface treatment, a new cerium chemical conversion coating was developed on 316L stainless steel through a mixed solution of hydrated cerium nitrate, citric acid, and hydrogen peroxide. The chemical composition was characterized by energy‐dispersive spectroscopy, X‐ray photoelectron spectroscopy and atomic force microscope. The dense conversion coating is composed of CeO2 with a small amount of Ce2O3 and has small grain size lower than 50 nm. Its thickness is about 47.4 nm as determined by spectroscopic ellipsometry analysis. Potentiodynamic polarization was used to study the corrosion behavior of the coatings in the concentrated artificial seawater at 72 °C. In comparison with the conventional nitric acid‐chromate passivated specimens, the cerium conversion coatings show much higher pitting potentials. It is suggested that the cerium conversion treatment is more effective than the nitric acid‐chromate passivation to improve the pitting resistance of 316L stainless steel used in the hot seawater environments.

A high temperature is produced in the process of precision milling of titanium alloy, and the cutting temperature can be effectively reduced by placing a micro-texture on the tool surface. In order to study the milling temperature of micro-textured ball-end milling cutter in milling titanium alloy under the combined action of a blunt radius with different edges and a micro-texture with different parameters, a new method based on micro-element theory and the generation and transmission of cutting heat has been established. At the same time, the influence of different radii of blunt edges on the milling temperature is simulated by the finite element method and experimentally verified to explore the influence of different radii of a blunt edge and micro-texture parameters on the milling temperature. Taking the milling temperature as the evaluation index, the optimum parameters of micro-circular pit texture are as follows: the diameter of micro-circular pit is 40 micron, pit spacing is 225 micron, distance from cutting edge is 100 microns, and radius of the blunt edge is 60 microns.