A review of the corrosion of laser nitrided Ti‐6Al‐4V

Abstract

PurposeThe purpose of this paper is to consider the corrosion properties of laser nitrided Ti‐6Al‐4V alloys that have been reported previously by several researchers.Design/methodology/approachDifferent kinds of surface nitriding methods of titanium alloys, such as plasma nitriding, ion nitriding, gas and laser nitriding, are introduced. Microstructure changes, such as phase formation and the influence of laser processing parameters in laser nitriding layers of Ti‐6Al‐4V alloys, were investigated using scanning electron microscope, transmission electron microscope, X‐ray photo‐electron spectroscopy, and X‐ray diffraction. Based on investigations presented in the literature, the effect of laser nitriding on the corrosion behavior of Ti‐6Al‐4V alloy was reviewed.FindingsBy regulating the laser processing parameter, the microstructure of the nitrided layer can be controlled to optimize corrosion properties. This layer improves corrosion behavior in most environments, due to the formation of a continuous TiNxOy passive film, which can retard the ingress of corrosive ions into the substrate and can maintain a constant value of a current density. Therefore, the laser gas nitrided specimens have a relatively noble corrosion potential and a very small corrosion current, as compared to untreated specimens.Originality/valueThis paper comprises a critical review, and its collection of references is useful. It summarizes current knowledge in laser surface treatment research.

Titanium Alloy Artillery Barrel and Radial Precision Forging Technology Discussion

“…Titanium was first discovered by the English chemist Gregor [1] It was first discovered in 1791 in Cornwall, England, while studying ilmenite, and was named titanium by the German chemist Klaproth. [2] In 1910, the American chemist Hunter [3] In 1910, the American chemist Hunter prepared titanium with a purity of 99.9%, and in 1932, the Luxembourg chemist Kroll [4] In 1932, Luxembourg chemist Kroll proposed the magnesium heat method to prepare pure titanium, and in 1947 titanium metal began to enter the industrial production stage, and after 1970 the annual production of titanium has maintained a steady growth rate of 15%.…”

A Review—Effect of Accelerating Methods on Gas Nitriding: Accelerating Mechanism, Nitriding Behavior, and Techno-Economic Analysis

“…In the process of surface laser treatment, the selection of parameters such as laser beam power, scanning speed, and scanning line distance can affect the depth and shape of the nitrided layer, thereby controlling the properties of the treated material. The main mechanism includes the following aspects [48][49][50]:…”

“…Figure 1 shows the application of accelerating nitriding in the field of wind power. Among these processes, process parameter optimization [18,37,38], surface mechanical nano-crystallization [39][40][41], surface active catalysis [42][43][44], surface pre-oxidation [45][46][47], and surface laser treatment [48][49][50] are relatively common accelerating nitriding methods. The development of accelerating nitriding methods is also expected to expand its application in other fields.…”