Selenium Copper Master Alloy, 7440-50-8, 7782-49-2

SELENIUM COPPER MASTER ALLOY 

1. PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

2. CHEMICAL STRUCTURE

2.1. Molecular Structure

Selenium Copper 40Se master alloy is an intermetallic compound of copper (Cu) and selenium (Se). The alloy consists primarily of the Cu₂Se intermetallic compound embedded in a copper-rich solid solution matrix. This structure provides a low liquidus temperature for easy dissolution and ensures rapid melting when added to molten copper.

Crystal Structure:

                    SeCu 40Se MASTER ALLOY
                               |
                    Cu₂Se + Cu-rich Matrix
                               |
             +----------------+----------------+
             |                |                |
         Cu₂Se Phase      Cu-rich Solid      Fine Selenium-
         (Intermetallic)   Solution          rich Phases

2.2. Phase Structure and Crystallographic Properties

2.3. Crystal Structure Details

2.4. Microstructure

The microstructure consists of a fine and homogeneous distribution of selenium-rich phases within a copper matrix. This uniform distribution ensures consistent alloying during dilution. The intermetallic Cu₂Se phase is finely dispersed, which facilitates rapid dissolution when the master alloy is added to copper melts.

3. PRODUCT QUALITY AND TYPICAL PROPERTIES

Note: The "I" notation indicates an isothermal transformation (typically peritectic or congruent melting), where the alloy melts at a single temperature of approximately 1130 °C under equilibrium conditions. This narrow melting range ensures rapid and homogeneous dissolution in copper melts.

4. CHEMICAL COMPOSITION

Maximum Impurity Levels (weight %):

Note: Full trace element analysis is provided with the certificate for each heat.

5. PHYSICAL PROPERTIES

6. METALLURGICAL PROPERTIES

Phase Structure:

• Cu₂Se intermetallic compound and copper-rich solid solution

• Provides low liquidus temperature for easy dissolution

• Ensures rapid melting when added to copper melts

Dissolution Rate:

• Rapidly dissolves in liquid copper above 1150 °C

• High selenium yield (>95%)

• Minimum slag formation

Microstructure:

• Fine and homogeneous distribution of selenium-rich phases within copper matrix

• Consistent alloying during dilution

• Uniform selenium distribution in the final alloy

7. ADVANTAGES AND APPLICATION AREAS

Advantages

Applications

8. ALLOYING MECHANISM

8.1. Effects of Selenium Addition

8.2. Reaction Mechanism

During master alloy addition to molten copper:

Cu (liquid) + Cu₂Se (master alloy) → Cu-Se (homogeneous melt)

The master alloy dissolves rapidly, releasing selenium which distributes uniformly throughout the melt. The Cu₂Se intermetallic breaks down and the selenium dissolves in the copper matrix or forms fine, dispersed Cu₂Se particles depending on the cooling rate and final composition.

9. RECOMMENDED MELTING PRACTICE

Yield Expectation:

• Expected selenium recovery >95% under normal conditions

• Adjust charge calculations accordingly

10. PACKAGING

11. STORAGE AND HANDLING

Storage:

• Store in a dry, closed, and well-ventilated area

• Avoid contact with water, moisture, and acids to prevent surface oxidation and formation of toxic selenium compounds

• Ambient temperature storage is acceptable; no special temperature control required

• Shelf life is unlimited under proper storage conditions

• Surface discoloration may occur over time but does not affect product performance

Handling:

• Use lifting equipment appropriate for pallet weight

• Avoid dropping to prevent damage to ingots or packaging

12. HEALTH, SAFETY AND ENVIRONMENT

Hazard Classification:

• The solid alloy presents minimal hazard

• During melting or grinding, selenium-containing fumes, dust, and vapors may be released

• Selenium compounds are toxic when inhaled and ingested

Preventive Measures:

First Aid:

Environment:

• Do not discharge residues into water or soil

• Dispose of waste in accordance with local regulations

For complete safety information, refer to the Safety Data Sheet (SDS) provided with the product.

13. QUALITY CONTROL

14. REGULATORY COMPLIANCE

15. QUICK REFERENCE TABLE

16. CRITICAL NOTICES AND BEST PRACTICES

CRITICAL NOTICES:

1. Toxic Fumes: Selenium-containing fumes, dust, and vapors are toxic when inhaled. Use adequate ventilation and respiratory protection during melting and grinding operations.

2. Acid Contact: Avoid contact with acids as toxic hydrogen selenide gas (H₂Se) may be formed.

3. Isothermal Melting: The alloy melts at a single temperature (1130 °C) ensuring rapid dissolution. No preheating is required but can accelerate dissolution.

4. High Yield: Expected selenium recovery >95%. Adjust charge calculations accordingly.

5. Lead-Free Alternative: Selenium acts as an effective substitute for lead in free-cutting copper alloys, providing an ecological solution.

6. Environmental Protection: Prevent fine particles and residues from entering water bodies.

BEST PRACTICE RECOMMENDATIONS:

Storage:

• Store in a dry, closed, well-ventilated area

• Avoid contact with water, moisture, and acids

• No special temperature control required

• Shelf life is unlimited under proper conditions

Handling:

• Use heat-resistant gloves, protective goggles, and flame-retardant clothing

• Use appropriate lifting equipment for pallets

• Avoid dropping to prevent damage

Melting:

• Preheat copper charge to minimum 1150 °C

• Add master alloy directly to the bath

• Gently stir for homogeneity

• Expected selenium recovery >95%

Waste Management:

• Do not discharge into sewers or water bodies

• Dispose in accordance with local regulations

LEGAL DISCLAIMER

The information in this Technical Data Sheet is based on our current knowledge and experience and is provided for general guidance only. It does not constitute a warranty of specific properties or suitability for any particular application. Since conditions of use are beyond our control, the user is responsible for determining the suitability of the product for their intended use and for complying with all applicable regulations. No express or implied warranties are given. This document does not supersede binding contractual specifications. For complete safety, storage, handling, transport, waste, and regulatory compliance information, the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier must be consulted.