Composition and Properties

Titanium-iron is a special alloy with wide applications. During steelmaking, workers add it as an alloying element. It refines steel’s microstructure and grains, fixes interstitial elements (C, N), and boosts steel strength. When smelting stainless steel and heat-resistant steel, titanium combines with carbon to form stable compounds. This prevents chromium carbide formation, reduces intergranular corrosion, and improves the weldability of chromium-nickel stainless steel. Products from titanium deoxidation tend to float. Using titanium to deoxidize killed steel reduces segregation in the upper part of the steel ingot. This improves ingot quality and increases ingot yield. Titanium combines with dissolved nitrogen in molten steel to form stable titanium nitride, which does not dissolve in molten steel. High-titanium iron is also an essential alloy material for smelting iron-based superalloys and high-quality stainless steel. Titanium-iron is an iron alloy mainly composed of titanium and iron. It also contains impurities like aluminum, silicon, carbon, sulfur, phosphorus, and manganese. In steelmaking, it works as a deoxidizer, desulfurizer, degasser, and alloying agent. Based on titanium content, it has three main types: FeTi30 (Ti 25.0%-35.0%, Al <8.5%, Si <5.0%), FeTi40 (Ti 35.0%-45.0%, Al <9.5%, Si <4.0%), and FeTi70 (Ti 65%-75%, Al 0.5%-5%, Si <0.5%).

Production Process

  • Remelting method

The remelting method uses titanium scrap and scrap steel as raw materials. It remelts them in an induction furnace to produce titanium-iron with about 70% Ti (the Fe-Ti series has a low eutectic point at around 68% Ti). To reduce titanium burn loss during remelting, workers put titanium waste into steel cylinders and compact it. Then they add a mixture of barium chloride and sodium chloride, cryolite, or a similar low-melting mixture as flux to cover the titanium-iron melt. This method can also produce various titanium composite alloys.

  • Electric silicon thermal method

The electric silicon thermal method uses ferrosilicon to reduce the TiO₂-FeO-CaO-CaF₂ melt in an electric furnace. It can produce composite alloys like Fe-Ti-Si and Si-Ca-Ti. Adding other oxides or iron alloys lets you make multi-component titanium composite alloys.

  • Electrocarbon thermal method

In a small electric furnace, using coke as the reducing agent and lime as the flux, high-carbon titanium iron with i20% to 25%, C5% to 8%, Sil% to 2%, Al1% to 2%, and a surplus of iron can be produced. To obtain titanium iron with a lower carbon content, silica can be added to the charge. If the composition of the charge is as follows: 47% ilmenite (tio2 251.5%), 28.5% silica, and 24.5% coke chips, medium-carbon ilmenite with Ti29% to 30%, Si17% to 20%, and C1.8% to 2% can be produced. By increasing the proportion of silica in the charge, low-carbon high-silicon titanium iron with about 30% Si and 0.1% to 0.3% C can be produced. If bauxite is added to the charge, Ti-Al-Si-Fe composite alloy can be smelted.

Main Uses

1. Steel metallurgy: It acts as a deoxidizer and alloying agent. It refines steel’s grain structure, enhances its strength, toughness, and corrosion resistance, and is often used to make stainless steel and ship plate steel.

2. Aerospace: It is a raw material for titanium alloys (e.g., Ti-6Al-4V). It is used to manufacture lightweight parts like aircraft engine blades and fuselage structural components.

3. Chemical engineering and electronics: High-purity titanium-iron powder can be processed into sputtering targets for semiconductor coatings. It can also serve as a catalyst or catalyst carrier.

4. 3D printing: It is a raw material for metal additive manufacturing (e.g., SLM technology). It is used to print complex titanium alloy parts.