Analysis of the Whole Recycling Chain of Titanium Scrap: Source Composition and Classification System
China's output of titanium dioxide, titanium sponge, titanium ingots and titanium processed materials reached 4.76 million tons, 256,000 tons, 190,000 tons and 172,000 tons respectively in 2024, all registering double-digit growth. Restricted by the relatively low yield rate of titanium products, the output of titanium scrap keeps rising. Recycling and reutilization have become a core approach for the titanium industry to conserve resources, boost production and cut costs.
As mentioned in the previous article “The Recycling Dilemma of Space Metal: Why Is Titanium's Recycling Rate Less Than One-Third of Scrap Steel？” titanium currently has a low recycling rate. This paper focuses on analyzing part of the titanium scrap recycling chain.
I. Core Sources of Titanium Scrap
Titanium scrap is mainly generated from production processes and end-of-life consumption, covering the full life cycle from raw materials to finished products.
1. Scrap Generated in Production
- Titanium sponge production: The surface, bottom and side crusts of titanium sponge ingots are contaminated by impurities, accounting for 6%–8% of total ingot weight. Such scrap is mostly used as additives for steelmaking and grain refiners for aluminum processing. Selected qualified scrap can serve as raw materials for smelting. Crushed titanium powder is applied to titanium filters and fireworks, while hydrogenated titanium powder is used in spray metallurgy and ferrotitanium production.
- Titanium ingot production: Trimming and peeling waste takes up 4%–5% of ingot weight. Smelting waste includes residual electrodes and oxide slag with titanium purity below 95% and requires purification. Forming waste such as risers and surface layers features stable composition and high recycling value. Substandard ingots eliminated after quality inspection can be recycled after targeted treatment.
- Titanium material processing: The overall yield rate ranges from 65% to 85%. Forging produces trimmed edges and oxide scales. Rolling and extrusion generate offcuts, making up 30%–40% of processing scrap. Machining chips account for 50%–60% of total waste and are often mixed with oil and cutting fluid. Defective finished products with high purity also constitute valuable recyclable materials. The calculated yield rate of domestic Titanium Materials stood at about 90.5% in 2024, affected by statistical caliber differences.
- Titanium product manufacturing: This is the largest source of titanium scrap, with processing loss hitting 40%–60%. The material utilization rate of TC4 Titanium Alloy for mobile phone frames is merely 15%, and that for watch cases ranges from 20% to 25%. Main waste includes machining chips, stamping offcuts and defective semi-finished products, which need decontamination before recycling.
2. End-of-Life Scrap from Consumption
Industrial waste covers retired aerospace components, chemical titanium equipment and medical implants. Civil waste includes titanium spectacle frames, watch cases and water bottles, boasting stable quality and higher market value.
In 2022, global titanium scrap volume totaled 281,000 tons, with end-of-life scrap occupying 12.6%. China produced 109,000 tons of titanium scrap, where end-of-life scrap only accounted for 1.8%. The small proportion is attributed to the short development history of domestic titanium industry and the long service life of titanium products. The service life lasts 20–30 years for aerospace parts, 15–20 years for marine and chemical facilities, 10–15 years for medical implants and 2–3 years for consumer electronic shells.
II. Classification System of Titanium Scrap
Classified by shape, source, quality and chemical composition in accordance with national and industrial standards, titanium scrap categories are shown in the table below:
| Classification Dimension | Category | Features | Proportion & Application |
| Shape | Block scrap | Large pieces over 100mm and small pieces below 100mm, including rolling offcuts | 30%–40%, easy to recycle and remelt directly |
|
| Chip & powder scrap | Turning, milling and drilling chips, generally processed below 100mm | Over 50%, prone to oxidation with complex treatment |
|
| Tubular & mesh scrap | Hollow and special-shaped structures such as titanium pipes and meshes | Recycled for dedicated industrial equipment |
| Source | Process scrap | Offcuts generated during forging, rolling and ingot casting | 98.2% of domestic scrap, major recycled material |
|
| End-of-life scrap | Retired industrial and daily products | 12.6% of global volume, less than 2% domestically |
| Quality Grade | Grade I scrap | Clean surface free of oil, inclusions and welding seams | High-quality raw material for reproduced products |
|
| Grade II scrap | Allowed with thermal oxidation scale, other indicators same as Grade I | Common recycled raw material |
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| Grade III scrap | Unqualified composition or defective metallurgical structure, used for low-end production | Low-value recycled material |
| Chemical Composition | Pure titanium scrap | Titanium content ≥99%, mainly TA1 and TA2 | Civil products and titanium powder production |
|
| Titanium alloy scrap | TC4, TA15 and other alloy materials | Aerospace industry, requiring strict sorting |
|
| Coated titanium scrap | Surface coated with iridium, platinum or ruthenium, mostly electrolytic electrodes | High-value recycling |
Global pure titanium scrap is graded CP1 to CP4 and industrial grade. CP1 with the highest purity is applied to aerospace and medical devices. CP2 to CP4 are widely used in construction, chemical industry and high-strength equipment. Industrial grade mixed scrap is adopted for cost-effective manufacturing.
Conclusion
Titanium scrap has concentrated sources and clear classification. Process scrap dominates current recycling volume, while end-of-life waste will increase steadily as products reach retirement age. Standardized classification, precise sorting and efficient treatment are essential to improve recycled titanium quality and cut industrial costs. With advancing recycling technology and optimized circular economy system, titanium scrap will evolve from production by-products into strategic renewable resources, facilitating the green, low-carbon and high-quality development of China’s titanium industry.