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Article
Publication date: 1 August 2002

A.M. Baraka, H.A. Hamed and H.H. Shaarawy

The electrodeposition of any metal over titanium substrates meets with many problems due to the formation of a non‐conductive layer of titanium oxide on the surface of substrates…

1224

Abstract

The electrodeposition of any metal over titanium substrates meets with many problems due to the formation of a non‐conductive layer of titanium oxide on the surface of substrates during the electroplating process. Trials were made to overcome these problems by the pre‐anodisation of titanium substrates in oxalic acid solution of concentration 100g/l, at high current density of 60‐95mA/cm–2, and at ambient temperature. In these conditions, a thin, porous and conductive titanium oxide film can be obtained, which will then support electroplating processes. Rhodium metal was electrodeposited over the anodised titanium substrates from a bath consisting of Rh2(SO4)3, 5.2g/l and H2SO4, 100g/l. At optimum conditions of electroplating, the rhodium electrodeposits were formed over the anodised titanium substrate with high adhesion, brightness and high current efficiency (92.05 per cent).

Details

Anti-Corrosion Methods and Materials, vol. 49 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 11 January 2011

Nivin M. Ahmed and Mohamed M. Selim

Kaolin is a soft, white mineral mainly composed of coarse‐ to fine‐grained, plate‐like aluminum silicate particles. As kaolin assists with desired rheological properties that help…

1183

Abstract

Purpose

Kaolin is a soft, white mineral mainly composed of coarse‐ to fine‐grained, plate‐like aluminum silicate particles. As kaolin assists with desired rheological properties that help maintain proper dispersion and provide bulk to the product, it is used as an important extender in paint manufacture. It can be used to reduce the amount of expensive pigments, such as titanium dioxide. In spite of these uses, kaolin has the disadvantage of having coarse particles and low hiding power. The purpose of this paper is to introduce a new class of pigments based on kaolin as a core and titanium dioxide as the shell.

Design/methodology/approach

In the work reported in this paper, kaolin was used as a core covered with a surface layer of titanium dioxide comprising the shell in order to combine their properties and get over kaolin's disadvantages, besides enhancing its corrosion protection properties. The pigments prepared were characterised using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Deposition of titanium dioxide on the surface of kaolin was confirmed by Energy‐dispersive X‐ray analysis (EDAX) and X‐ray fluorescence (XRF) techniques. Pigment properties were estimated according to American standard testing methods (ASTM) methods and then were incorporated in anticorrosive paint formulations based on medium oil alkyd resin. The physico‐mechanical and corrosion properties of dry paint films were determined according to ASTM methods.

Findings

The tests revealed that the concentration of titanium dioxide layer deposited on kaolin surface was inversely proportional to the anticorrosive behaviour of these pigments.

Practical implications

The pigments can be applied in other polymer composites, e.g. rubber and plastics as filler and reinforcing agent.

Originality/value

The pigments prepared are eco‐friendly that can replace other expensive pigments. These pigments can compensate for the presence of titanium dioxide in paint formulations successfully, and thus lower the costs. The main advantage of these pigments is that they combine the properties of both of their counterparts, they are of lower cost, and they also overcome the disadvantages of both its counterparts, e.g. low hiding power of kaolin, photochemical activity of titanium dioxide. Also, they can be applied in other industries other than paints, e.g. paper, rubber and plastics composites.

Details

Pigment & Resin Technology, vol. 40 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 September 1974

Heinz Rechmann

Over the last 50 years the element titanium has been steadily gaining in importance. The major interests range from titanium metal, which combines good resistance to corrosion…

Abstract

Over the last 50 years the element titanium has been steadily gaining in importance. The major interests range from titanium metal, which combines good resistance to corrosion with high strength and low specific gravity, to the white pigment, titanium dioxide, and titanium tetrachloride, a chemical intermediate. This paper reviews the manufacture of these materials and particularly deals with the properties and applications of titanium dioxide, which, by reason of its high refractive index, possesses outstanding lightening and hiding power, making it the first choice among white pigments.

Details

Pigment & Resin Technology, vol. 3 no. 9
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 June 1989

Z.A. Foroulis

Aqueous solutions which contain H2SO4, H2S or mixtures of H2S and NH3 are corrosive to carbon steel and other commonly used alloys. Therefore, titanium has been evaluated as a…

Abstract

Aqueous solutions which contain H2SO4, H2S or mixtures of H2S and NH3 are corrosive to carbon steel and other commonly used alloys. Therefore, titanium has been evaluated as a possible construction material in these environments. This paper summarizes the results of a study of the corrosion, galvanic and hydrogen embrittlement behaviour of titanium in aqueous sulfidic and sulfate solutions. Variables discussed include the effect of solution pH, temperature and solution composition on the corrosion and electro chemical behaviour including galvanic effects of titanium. This paper also considers the effect of pH, temperature and mechanical loading rate (strain‐rate) on the ductility and embrittlement of titanium.

Details

Anti-Corrosion Methods and Materials, vol. 36 no. 6
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 17 March 2012

Boqiong Li, Zhiqiang Li and Xing Lu

Porous titanium is used in many bioimplant and electrode applications because of its interconnected pore structure and good corrosion resistance. The purpose of this paper is to…

Abstract

Purpose

Porous titanium is used in many bioimplant and electrode applications because of its interconnected pore structure and good corrosion resistance. The purpose of this paper is to study the anodic polarization behavior of porous titanium in different electrolytes and clarify the influences of the porosity and macro‐pore size on the corrosion resistance.

Design/methodology/approach

The porous titanium with 10‐70% porosities and average macro‐pore sizes in the range of 100‐500 μm was prepared by the powder metallurgy method using polymethyl methacrylate (PMMA) as a space holder. Electrochemical corrosion tests were performed on porous titanium as well as solid titanium (with the same irregular and isolated micro‐pore structures as that on the interconnected spheroidal macro‐pore walls of porous titanium) in the 0.1 M H2SO4, 1 M NaOH and 0.9% NaCl (37 °C) solutions.

Findings

It was found that porous titanium exhibited an active‐passive transition behavior in the 1 M NaOH and 0.1 M H2SO4 solutions. In contrast, a self‐passivation transition behavior was observed in the 0.9% NaCl solution (37 °C).

Originality/value

The paper demonstrates that both the porosity and macro‐pore size of porous titanium play an important role in determining the corrosion rate, rather than the corrosion potential.

Details

Anti-Corrosion Methods and Materials, vol. 59 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Open Access
Article
Publication date: 20 March 2024

Guijian Xiao, Tangming Zhang, Yi He, Zihan Zheng and Jingzhe Wang

The purpose of this review is to comprehensively consider the material properties and processing of additive titanium alloy and provide a new perspective for the robotic grinding…

Abstract

Purpose

The purpose of this review is to comprehensively consider the material properties and processing of additive titanium alloy and provide a new perspective for the robotic grinding and polishing of additive titanium alloy blades to ensure the surface integrity and machining accuracy of the blades.

Design/methodology/approach

At present, robot grinding and polishing are mainstream processing methods in blade automatic processing. This review systematically summarizes the processing characteristics and processing methods of additive manufacturing (AM) titanium alloy blades. On the one hand, the unique manufacturing process and thermal effect of AM have created the unique processing characteristics of additive titanium alloy blades. On the other hand, the robot grinding and polishing process needs to incorporate the material removal model into the traditional processing flow according to the processing characteristics of the additive titanium alloy.

Findings

Robot belt grinding can solve the processing problem of additive titanium alloy blades. The complex surface of the blade generates a robot grinding trajectory through trajectory planning. The trajectory planning of the robot profoundly affects the machining accuracy and surface quality of the blade. Subsequent research is needed to solve the problems of high machining accuracy of blade profiles, complex surface material removal models and uneven distribution of blade machining allowance. In the process parameters of the robot, the grinding parameters, trajectory planning and error compensation affect the surface quality of the blade through the material removal method, grinding force and grinding temperature. The machining accuracy of the blade surface is affected by robot vibration and stiffness.

Originality/value

This review systematically summarizes the processing characteristics and processing methods of aviation titanium alloy blades manufactured by AM. Combined with the material properties of additive titanium alloy, it provides a new idea for robot grinding and polishing of aviation titanium alloy blades manufactured by AM.

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2633-6596

Keywords

Article
Publication date: 1 June 1976

B.H. Hanson

Introduction Titanium is becoming increasingly widely used in the oil industry in such areas as exploration/production, pipelines, underwater operations, engineering/construction…

Abstract

Introduction Titanium is becoming increasingly widely used in the oil industry in such areas as exploration/production, pipelines, underwater operations, engineering/construction and refining. The applications mainly depend on the unique corrosion resistance of the material in seawater but some use is made of the high specific strength of titanium alloys and also of their excellent resistance to cavitation and erosion. Potential and established uses of titanium include tube‐in‐shell and plate type heat exchangers, equipment for data logging, tanker purge systems, pumps and valves, fixtures and fittings, cathodic protection anodes and submersibles for underwater operations.

Details

Anti-Corrosion Methods and Materials, vol. 23 no. 6
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 26 July 2021

Zhong Li, Xiaojia Yang, Jing Liu, Zhiyong Liu, Xiaogang Li and Yan Tingting

The purpose of this paper is to determine the failure reasons and failure mechanism of the commercially pure titanium air conditioning condenser.

Abstract

Purpose

The purpose of this paper is to determine the failure reasons and failure mechanism of the commercially pure titanium air conditioning condenser.

Design/methodology/approach

In this paper, chemical analysis, metallographic observation, visual examination and scanning electron microscope examination, corrosion products analysis and working conditions analysis were adopted for determining the reasons for the failure of the condenser.

Findings

The results indicated that TA2 titanium pipe perforation failure is caused by the synergistic effect of crevice corrosion and deposit corrosion. The corrosion processes can be divided into three steps.

Originality/value

This research is an originality study on the failure case of a commercially pure titanium air conditioning condenser. This study makes up for the shortage of titanium alloy failure cases and also gives the result of the failure reason and failure mechanism for titanium, which has an engineering significance.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 April 1979

H. KRAUSE and J. SCHOLTEN

CONTINUAL pressure of competition from the aircraft and automobile industries is forcing the administrators of railways throughout the world to concentrate their efforts on…

Abstract

CONTINUAL pressure of competition from the aircraft and automobile industries is forcing the administrators of railways throughout the world to concentrate their efforts on possibilities of modernization and improvement, with particular emphasis on the increase in travelling speeds. It is, therefore, necessary to pay special attention to the system railway wheel/rail, as it is this which has to fulfil such important functions as transmitting the driving, braking and guiding forces, quite apart from supporting the vehicle itself.

Details

Industrial Lubrication and Tribology, vol. 31 no. 4
Type: Research Article
ISSN: 0036-8792

Article
Publication date: 1 January 1996

Andrew Bacon

Comments on the results of a survey into the use of titanium in the offshore industry. The results revealed that a major lack of knowledge appears to exist among marine engineers…

Abstract

Comments on the results of a survey into the use of titanium in the offshore industry. The results revealed that a major lack of knowledge appears to exist among marine engineers when it comes to what the exact properties and uses of titanium really are. Highlights the benefits of titanium for the offshore industry.

Details

Anti-Corrosion Methods and Materials, vol. 43 no. 1
Type: Research Article
ISSN: 0003-5599

1 – 10 of over 4000