Which Three Hot Extrusion Processes Optimize Titanium Rod Production?

Titanium rods  are core products of titanium processed materials, and their manufacturing processes directly determine the microstructure, performance and application of the products. Hot extrusion is an important plastic working method for titanium and titanium alloys. Realizing forming under high temperature and high pressure, it features strong deformability, high quality and wide applicability. Forming hot extrusion, sintering hot extrusion and hot working hot extrusion are the mainstream processes for titanium rods.

 

 

As the most fundamental and commonly used production process for titanium rods, forming hot extrusion can directly extrude titanium billets into rods under high temperature and high pressure. It boasts a concise process, precise forming and low subsequent machining allowance.

 

Core Process

• Pretreatment: Clean the billets and, if necessary, perform jacket vacuum sealing to prevent high-temperature oxidation.
• Heating: Control the temperature according to the type of titanium alloy, and conduct extrusion for different alloys within the corresponding temperature ranges.
• Extrusion: Achieve forming under high pressure in an extruder, with strict control over extrusion speed and ratio to avoid defects.
• Cooling: Adopt air cooling or slow cooling as the main methods to reduce internal stress and prevent deformation and cracking.

 

Advantages

High efficiency, excellent dimensional and surface quality, simple process and relatively low cost.

 

Limitations

High requirements for billets, inapplicable to complex cross-sections, high extrusion difficulty for high-strength titanium alloys, and the need for large-scale equipment.

 

Applications

It is mostly used for conventional-specification, medium-strength titanium rods for civil use, such as those applied in chemical equipment and general structural components.

 

 

Sintering hot extrusion is a composite process for titanium powder or porous titanium billets, which combines sintering with hot extrusion. It first realizes densification through sintering and then achieves strengthening via extrusion, solving the problems of insufficient densification and strength in single powder forming/sintering.

 

Process

• Raw material preparation: Select high-purity titanium/titanium alloy powder for sieving and mixing.
• Forming: Cold-press the powder into porous billets.
• Sintering: Conduct heat preservation at 800–1200℃ in a vacuum or protective atmosphere to realize particle bonding and densification.
• Hot extrusion: Perform heating followed by extrusion to eliminate residual pores and refine grains.
• Post-treatment: Conduct surface cleaning and heat treatment to optimize performance.

 

Advantages

High densification, uniform microstructure, fine grains and superior mechanical properties; high raw material utilization rate, enabling the preparation of high-end titanium alloy rods.

 

Limitations

Complex process, long cycle, difficult parameter control, high requirements for equipment and technology, and relatively high cost.

 

Applications

It is mostly used for titanium rods in high-end fields such as aerospace and biomedicine.

 

 

Hot working hot extrusion is a dynamic plastic working process that simultaneously achieves deformation and microstructure optimization during hot extrusion. It realizes customized mechanical properties by regulating temperature, pressure and speed, and is the most flexible and adaptable one among the three processes, often used in combination with processes such as rotary swaging.

 

Its process is similar to that of forming hot extrusion, but with a greater focus on microstructure control:

• Pretreatment: Clean and jacket the billets; pre-heat treatment can be conducted if necessary to optimize the initial microstructure.
• Heating: Adopt sectional heating and gradient heat preservation to ensure uniform microstructure and deformation.
• Extrusion: Dynamically adjust process parameters to realize grain refinement and recrystallization.
• Cooling: Select cooling methods on demand to precisely control the strength and toughness of products.
• Post-treatment: Conduct aging and polishing to improve performance and surface quality.

 

Advantages

Controllable performance, high flexibility and customizable mechanical properties; few internal defects and high reliability; wide applicability to materials and specifications, capable of producing titanium rods with complex cross-sections.

 

Limitations

Complex process parameters, high requirements for equipment and operation; relatively low efficiency and high cost.

 

Applications

It is mostly used for customized titanium rods with high performance requirements in high-end equipment, aerospace, military industry and other fields.

 

 

 

Forming hot extrusion: Focuses on shape control, featuring a simple process and high efficiency, and is applicable to conventional titanium rods with medium performance.

 

• Sintering hot extrusion: Focuses on densification and high performance, and is suitable for titanium rods made from powder raw materials and high-end titanium rods.
• Hot working hot extrusion: Focuses on customization and microstructure optimization, with high flexibility, and is used for titanium rods with special performance requirements and complex cross-sections.
• The selection of processes is based on performance, specification, raw materials and cost:
• For ordinary civil titanium rods with medium strength: Forming hot extrusion is adopted.
• For high-end, high-performance titanium rods or those made from powder raw materials: Sintering hot extrusion is adopted.
• For customized titanium rods used in aerospace, military industry and other fields: Hot working hot extrusion is adopted.