Influence of Titanium Surface Porosity on Adhesive Strength of Coatings Containing Calcium Silicate.

Ivan Zhevtun,Sofia Yarusova,Yury Kulchin,Vadim Timchenko,Pavel Nikiforov,Dmitry Pivovarov,Alexander Nikitin,Pavel Gordienko,Andrey Golub

doi:10.3390/ma13204493

Ivan Zhevtun, Sofia Yarusova + Show 7 more

Open Access

https://doi.org/10.3390/ma13204493

Copy DOI

Abstract

Titanium-based alloys are widely used in aerospace engineering. They have good mechanical and corrosion properties but, in some cases, the material itself or the coating should meet some additional requirements. For example, it may be a requirement of high reflectance to provide effective temperature control. Wollastonite is a promising component for reflective coatings because it improves both their whiteness and mechanical properties. This paper presents the results of studying the composition, the structure and the adhesive strength of wollastonite-containing silicate coatings to titanium substrate. The surface of titanium samples was pre-treated by laser cladding with TiC and etching to provide surface porosity. It has been shown that such treatment allows a significantly increase in the adhesive strength of the coating to the substrate. A decrease in the adhesive strength was observed on titanium samples with an excess of TiO2 on the surface. This is caused by the formation of crystalline PbTiO3 at the interface.

Highlights

Titanium and its alloys are widely applied as construction materials in many fields, including aerospace engineering
As a result of laser cladding with titanium carbide powder and subsequent selective etching in nitric acid, surface porosity can be formed on titanium substrate
After the treatment according to this mode, a homogeneous network of nanosized pores was formed on the inner surface of micropores (Figure 1 c–f)

Summary

Introduction

Titanium and its alloys are widely applied as construction materials in many fields, including aerospace engineering. Pure titanium and some its alloys do not embrittle even in liquid helium, while another titanium alloys may be applied at temperatures up to 600 ◦ C. They have higher specific strength than many other construction materials [1,2]. While using titanium alloys for creating spacecrafts, special coatings with high reflection coefficients may be required to provide better temperature control. Common pigments for such coatings are metal oxides such as ZnO, TiO2 , Al2 O3 , ZrO2 or spinels such as Zn2 TiO4 , MgAl2 O4 [3,4,5]

Objectives

Methods

Results

Conclusion