UL 1690 DO
A 90% silicon carbide deoxidizer for clean-steel production under secondary-refining conditions.
UL-1690-DO is a 90% silicon carbide (SiC ≥ 90%) deoxidizer designed for secondary refining. It delivers deep deoxidation and cleanliness control in EAF and LF routes for alloy and clean steel.
What it is
What UL 1690 DO Is & Where It Is Used
UL 1690 DO is a 90% silicon carbide deoxidizer with total carbon of 28–32%. With low free carbon (≤ 2.2%), low silica (≤ 8%), and tightly controlled impurity levels, it is built for secondary refining rather than crude melting.
It is applied in EAF and LF refining of alloy steel and clean steel, where deep deoxidation and inclusion control decide the final quality. Lump (10–50 mm) and powder (200#–0) forms are supplied to match the process.
Deoxidation Mechanism
Deoxidation Mechanism
UL 1690 DO deoxidizes through the same core reaction, but its low impurity profile makes it suitable for refining:
SiC + 3[O] → SiO₂ + CO↑. In refining the goal shifts from basic deoxidation to deep oxygen removal and inclusion control, so the near-pure SiC reacts cleanly without re-introducing harmful elements.
Low free carbon (≤ 2.2%) and low silica (≤ 8%) limit slag volume and secondary oxidation, helping reach the low oxygen and clean microstructure that alloy and special steels require.
Key Advantages
Key Advantages
UL 1690 DO is specified where cleanliness, not just cost, is the constraint:
Deep deoxidation
Low-impurity 90% SiC drives oxygen down during refining for cleaner steel.
Cleanliness control
Minimal free carbon and silica reduce inclusions and slag interference.
Refining-grade purity
Meets the tighter chemistry needed in EAF/LF secondary refining.
Alloy recovery
Stable reducing atmosphere supports consistent recovery of alloying elements.
Form flexibility
Supplied as 10–50 mm lump or 200#–0 powder to fit charging and injection.
Technical Specifications
Technical & Physical Specifications
Typical specifications for UL 1690 DO.
Technical & physical properties
| Item | Typical specification |
|---|---|
| SiC Content | ≥ 90% |
| Total Carbon Content | 28%–32% |
| Free Carbon | ≤ 2.2% |
| SiO₂ Content | ≤ 8% |
| Al₂O₃ Content | ≤ 1% |
| Fe₂O₃ Content | ≤ 2.3% |
| S Content | ≤ 0.05% |
| N Content | ≤ 0.05% |
| Moisture Content | ≤ 0.5% |
| Particle Size | 10–50 mm (lump) / 0–3 mm, 0–5 mm, 0–10 mm, 200#–0 (powder, customizable) |
| Appearance | Black |
Usage
Types Of 90 Silicon Carbide
Silicon Carbide Lumps (Metallurgical Grade)
10–50 mm dense, high-strength, dust-free lumps for smooth furnace feeding and uniform reaction. Sizes can be customized.
Silicon Carbide Powder (Casting Taphole Clay Grade)
200#–0 powder for anhydrous taphole-clay formulations in large blast furnaces, improving slag-erosion resistance and high-temperature strength.
Silicon Carbide Alloy
Combined deoxidation-and-carburization additive used in converter and ladle practice.
Applications
Applications
Special & alloy steels
Deep deoxidation and inclusion control in EAF/LF refining of alloy and special steels.
Blast furnace taphole clay
Core aggregate in anhydrous gunning mix for large blast furnaces, resisting slag erosion.
Refractory materials
Fills the matrix of refractory mixes, raising thermal-shock stability and erosion resistance.
Electric arc & converter furnaces
Deoxidation during reduction and tapping to maintain a clean reducing atmosphere.
Purification & deep deoxidation of special steel
Supports ultra-low oxygen and clean microstructure in demanding grades.
FAQ
UL 1690 DO — Frequently Asked Questions
A 90% SiC deoxidizer for EAF/LF secondary refining of alloy and clean steel, where deep deoxidation and inclusion control decide quality.
Its low free carbon (≤ 2.2%) and low silica (≤ 8%) avoid re-introducing impurities during refining, unlike crude-melt grades.
10–50 mm lump for charging and 200#–0 powder for taphole-clay and injection, both customizable.
By sustaining a stable reducing atmosphere it supports consistent recovery of alloying elements such as manganese and chromium.
Yes. The powder grade is a core aggregate in anhydrous gunning mix for large blast furnaces.
0–3 mm, 0–5 mm, and 0–10 mm powders are supplied; sizes are customizable to the feeding system.
Get Started
Specify Your UL 1690 DO Grade
Provide your refining route, steel grade, and required form (lump or powder) to FerrumX. The technical team recommends a specification and addition method for your furnace.
Related: Silicon Carbide · Black Silicon Carbide · Metallurgical Silicon Carbide · Silicon Carbide for Refractories · Taphole Clay · Silicon Carbide Grades
