Titanium Clad Steel Plates
Titanium is a superior corrosion and heat resistant metal. Titanium clad steel plates are made of common grade TA1 or TA2 combined with carbon steel or even alloy steel using the process of explosive welding along with hot rolling for smooth-surfaced plates. Titanium steel clad plates are cost-effective as compared to pure titanium; and, therefore, its application has increased in a wide range of industrial machinery and processes.
Production Methods of Titanium Clad Steel Plate:
Titanium clad steel plates possess not only the corrosion resistance and thermal conductivity of titanium metal, but also has the formability and weldability of steel. Consequently, it saves the expensive titanium metal and the clad plates are easily utilized in different industries.
However, the hardest challenge is to bond titanium with carbon steel to achieve an interface with a powerful bonding strength. Titanium has limited solubility in iron. Therefore, it forms brittle inter-metallic compounds such as Fe-Ti or TiC when it comes in contact with steel; thus, it reduces the interface bonding strength.
The different processes of cladding titanium with carbon steel have been developed including the explosive welding process, diffusion process, and explosion roll bonding process.
1. Explosive Welding
Introduced in the 1950s, the explosion cladding process is widely used in industry and has been refined over time at a global scale.
Explosive Welding (also known as Explosive Bonding or Explosive Cladding) is an industrial welding process that follows certain principles for accurate bonding. From a birds-eye view, it’s the employment of energy of explosive detonation for welding various metal plates together. The metallurgical bond can be created between different metal components that either metallurgically compatible or are non-weldable metals (when welded using conventional methods). The strength of the welding process can be determined by the fact that against one or both faces of the base metal, one or more layers of different metal types or alloys can be bonded.
The cladding process involves parallel installation method and the detonation methods utilized is the central detonation method. For symmetrical collision and high-quality welding, a certain gap is left by placing metal spacers in between the two plates, before exploding the composite plates.
Here is the process:
1. The Cladding Metal (Cladder)—the thin plate that is in contact with the explosive
2. The Base Metal—it bonds the cladding metal
3. The Standoff Distance—the separation between the base metal and the cladding metal is maintained in parallel before the bonding operation.
4. The Assembly Operation—the metals are fixed into a proper position parallel to each other before the final welding or bonding operation.
5. The Bonding Operation—the period when the explosive detonation occurs to bond the metals together.
The greatest advantage of the welding process is that it does not interfere with the thermal resistance or conductivity of the materials being cladded. Moreover, it can perfectly clad together with the non-weldable materials.
One of the downsides of explosive welding is the cost and labor required for the process. Also, due to the residual stress and plastic deformation, there can occur stress corrosion cracking in the interface.
2. Diffusion Bonding:
It requires the utilization of suitable interlayer to stop diffusion and prevent degradation of the bonding interface. It’s a time taking process but has failed to gain much attention in the industry because it can lead to brittle inter-metallics at the interface. Such brittleness can cause crevices and makes it prone to get damaged prematurely in a corrosive environment.
3. Explosion Roll Bonding Process:
The explosive welding process between two un-bondable materials was successful due to the high temperature and pressure created at the collision place. However, morphological changes at the interface led to the formation of brittle inter-metallics. Moreover, it was quite an expensive method. Therefore, the idea of interlayer was introduced that got accomplished by the explosion roll bonding process.
An explosion roll bonding process helps in attaining desirable bonding characteristics by adding a carefully selected buffer layer material and the rolling practice.
The explosion roll bonding process involves rolling of the composite multilayered metal at a high temperature of 1200 to 1600 F. A wavy interface is interspersed in between the titanium and steel layer that has pockets of alloys with a total bonding area of less than 15%. The composite is joined by explosive bonding.
The key challenge is the selection of an appropriate buffer material that prevents the formation of any brittle inter-metallic phase. When an appropriate and freshly developed interlayer is chosen, not only it prevents the formation of Fe-Ti bonds but also provides a high bonding strength as well as ductility in the bend tests.
Copper acts as a preferable choice as an interlayer due to its low melting point and high plasticity. Application of the copper interlayer prevents the formation of brittle compounds in the interface.
Explosion roll bonding process has made possible the manufacturing of titanium clad steel plates with a width of 1000 to 4000 mm and a length of 8,000 mm. On top of that, such large-sized clad plates have displayed a shear strength between 19 to 25 kgf/mm2. Titanium clad steel plates are easy to cut using gas flame or plasma arc cutting method. Manufacturing elliptical titanium clad steel head or titanium clad tube sheet has become a possibility as there is no chance of dis-bonding or surface cracks.
The roll cladding process ensures the production of superior quality cladding material so it has attracted great attention around the industry.
Advantages of Titanium Clad Steel Plates:
Titanium clad steel plates have the properties of low density, high strength, temperature resistance, and corrosion resistance. Before cladding of titanium into the steel plates, extremely high or low temperatures resulted in corrosion. Moreover, the Titanium clad steel plates can save the resources of titanium and is cost-effective for use in industry.
The Titanium clad steel plates are widely used in aerospace, metallurgical, chemical, aviation, and power sectors.
The corrosion-resistant titanium and high strength steel, when cladded together, make up an ideal formula for good thermal conductivity to overcome thermal stress, thermal fatigue resistance as well as pressure difference. The high strength achieved cost-effectively can withstand other loads under the highly demanding conditions.
Ultimately, titanium clad steel plate has turned out to be an indispensable structural material for employment in the petrochemical and power industries as well as the pressure vessel industry.
Application of Titanium Clad Plates in Flue-Gas Desulfurization (FGD)
Flue-gas desulfurization includes the process of removing sulfur dioxide (SO2) from the exhaust flue gasses being emitted by thermal power plants and from other sulfur oxide emitting processes.
During the FGD process in the wet scrubber, flue gasses flow through the chimney of the scrubber and corrosion may occur. For efficient and effective flue-gas desulfurization in the scrubber, titanium clad steel plates act as the perfect construction material for the internal cylinder of the chimney.
Therefore, chimneys are externally coated with cement but internally coated with titanium clad steel plates to prevent corrosion and for smooth running of the FGD process.
What Do We Offer?
We are importers of high-end, self-tested Titanium Clad Steel Plates manufactured by explosion roll bonding process. The manufacturing process dictates the surety of the non-brittle, high-strength, and easy-to-cut titanium clad steel plates.
As for our high quality supply range of Titanium Clad Steel Plates; we have the following variety available:
· The clad material used is Titanium Gr.2 ASTM B265 with a thickness range of 1.5mm to 20mm
· The base materials used are either SA516 Gr. 60 or SA516 Gr.70 with a thickness range of 2mm to 200mm
· The overall Titanium Steel Clad Plates available have a width up to 4000m and a length up to 8000mm
· Standard is ASTM B898
Why Choose Horizon Exports?
We ensure quality by running self-tests for each product that’s sent our way. After all, client satisfaction is our priority and for that purpose, we leave zero loopholes to attain perfection.
To contact us, email at exoticalloys@horizonexports.net
Prashant Mehta
Horizon Exports
Ahmedabad, India.