Material Safety Data Sheet (MSDS) for Molybdenum-Tungsten Alloy

1. Identification

Product Name: Molybdenum-Tungsten Alloy
Chemical Family: Refractory Metal Alloy
Synonyms: Mo-W alloy
Manufacturer / Supplier: Contact local producer or distributor for details
Emergency Contact: Refer to company-specific emergency line
Intended Use: High-temperature applications, electronics, aerospace parts, industrial machinery

2. Hazard Identification

Hazard Classification: Not classified under GHS for bulk alloy; dust may present health risks
Main Risks: Chronic inhalation exposure to fumes or dust may affect lungs; eye and skin irritation possible from dust
Pictograms: None for massive material; exclamation mark for dust or powder
Signal Word: Warning, for dust
Hazard Statements: May cause respiratory irritation (dust/fume); possible eye and skin irritation
Precautionary Statements: Avoid breathing dust or fumes; wear protective equipment where particulates form
Routes of Exposure: Inhalation, eye contact, skin contact, ingestion unusual and not expected during normal use
Environmental Hazards: Low; not classified as marine pollutant
Target Organs: Lungs, skin, eyes (for airborne particulates only)

3. Composition / Information on Ingredients

Molybdenum (Mo): 50–90% by weight
Tungsten (W): 10–50% by weight
CAS Number (Mo): 7439-98-7
CAS Number (W): 7440-33-7
Other Components: Trace impurities, below 0.1%
Alloy Type: Homogeneous solid solution, no hazardous decomposition under normal use

4. First Aid Measures

Inhalation: Move person to fresh air, get medical attention if symptoms develop (coughing, difficulty breathing)
Eye Contact: Rinse cautiously with water for several minutes; remove contact lenses; seek medical evaluation if irritation persists
Skin Contact: Wash with soap and water; use lotion if dryness occurs
Ingestion: Not expected; seek medical advice if unusual symptoms arise
Note to Physician: Treat symptomatically for particulate exposure

5. Fire-Fighting Measures

Flammability: Not flammable in solid form; dust may be combustible
Extinguishing Media: Use dry chemical, sand, or graphite; avoid water on powder fires
Special Hazards: Fine powder may produce metal oxide fumes
Firefighting PPE: Use self-contained breathing apparatus and full protective clothing
Explosion Risk: Fine dust in air may cause explosion hazard under strong ignition sources

6. Accidental Release Measures

Personal Precautions: Wear dust mask, safety glasses, and gloves
Environmental Precautions: Avoid release to waterways and drains
Spill Cleanup: Sweep or vacuum without raising dust; collect in appropriate container for disposal
Decontamination: Wash area with water when all material removed; avoid using compressed air
Disposal: Follow local hazardous waste rules

7. Handling and Storage

Handling: Minimize dust formation; use with adequate ventilation; avoid ingestion or inhalation
Hygiene: Wash hands after handling; do not eat, drink, or smoke near product
Storage Conditions: Store in dry, cool environment, away from strong acids and oxidizers
Packing Material: Use containers resistant to corrosion; label properly
Special Instructions: Keep away from combustible materials when handling dust or powder

8. Exposure Controls and Personal Protection

Occupational Exposure Limits: Molybdenum (insoluble compounds, TWA): 10 mg/m³ (ACGIH); Tungsten (insoluble compounds, TWA): 5 mg/m³ (ACGIH)
Engineering Controls: Ventilation (preferably local exhaust for dust)
Personal Protection Equipment: Safety glasses; impermeable gloves; particulate respirator for dust; long sleeves for skin contact prevention
Environmental Controls: Avoid aerosolization and water discharge

9. Physical and Chemical Properties

Appearance: Silver-gray metallic solid
Odor: None
Melting Point: 2600–2900°C, varies with composition
Boiling Point: Not applicable for solid alloy
Solubility: Insoluble in water
Density: 10.2–17.6 g/cm³ depending on W:Mo ratio
Vapor Pressure: Negligible at ambient temperature
Other Properties: High electrical and thermal conductivity; not volatile

10. Stability and Reactivity

Chemical Stability: Stable under normal temperatures and pressures
Conditions to Avoid: Strong oxidizers, mineral acids (possible corrosion or exothermic reactions with powder)
Incompatibilities: Chlorine trifluoride, fluorine gas, strong acids (for powder forms)
Decomposition Products: Metal oxides (fumes) under extreme heat or fire
Hazardous Polymerization: Does not occur

11. Toxicological Information

Acute Toxicity: Low for solid; inhalation of dust may irritate mucous membranes
Chronic Exposure: Possible signs include irritation, coughing, lung changes (for dust/fume); animal studies show low systemic toxicity
Skin/Eye Sensitization: Not expected for bulk; possible mild irritation from particulates
Carcinogenicity: Not identified as carcinogen by IARC, NTP, or OSHA
Mutagenicity: No evidence noted
Reproductive Effects: No adverse data for alloy components
Ingestion Risk: Unlikely route, low toxicity predicted

12. Ecological Information

Mobility in Soil: Low; remains as solid particulates
Persistence/Degradability: Not biodegradable; persists as metal
Bioaccumulation: Unlikely due to low solubility
Aquatic Toxicity: Negligible for bulk; dust may cause minor physical effects on aquatic life at high concentrations
Other Environmental Information: No known major impacts for alloy under typical use or accidental release

13. Disposal Considerations

Product Disposal: Send scrap or dust to permitted metal recycling or hazardous waste facility
Container Disposal: Ensure containers are empty or clean before recycling; dispose per local regulations
Precautions: Avoid landfill disposal for significant amounts of dust or chips
Authorities to Contact: Local environmental, state, or national hazardous waste offices

14. Transport Information

UN Number: Not regulated for bulk; for dust, may fall under UN3077 (Environmentally hazardous substance, solid, n.o.s.)
Transport Hazard Class: None for solid
Packing Group: Not assigned unless dust
DOT / IATA / IMDG: Not regulated for solid; dust may fall under environmentally hazardous class
Special Precautions: Keep package secure to avoid dust release

15. Regulatory Information

OSHA: Regulated for dust exposure under Particulates Not Otherwise Regulated (PNOR)
SARA Title III: Not listed as hazardous
TSCA Status: Components listed
REACH: Registration for substances may apply for powder forms
California Prop 65: Not listed
WHMIS (Canada): Not classified for massive form, Particulate may be D2A (chronic toxicity)
Other International Regulations: Check local standards for occupational and environmental health