Alloy W,Hastelloy W,UNS N10004,EFORU

### **Technical Datasheet: Alloy W (Hastelloy W, UNS N10004)** 

 **Overview** Hastelloy W (Alloy W, UNS N10004) is a nickel-molybdenum-chromium alloy specifically developed for exceptional resistance to hot hydrochloric and sulfuric acids. This solid-solution strengthened nickel-based alloy maintains good mechanical properties and structural stability in highly corrosive environments, particularly in chemical processing applications. 

 **Key Characteristics** 

- **Excellent resistance to hydrochloric acid

** at all concentrations and temperatures 

- **Good resistance to sulfuric acid** 

and other reducing chemicals 

- **Outstanding corrosion resistance

** in acidic and alkaline media 

- **Good fabricability** 

and weldability 

- **Resistance to stress corrosion cracking** 

1. Chemical Composition (Weight %)**

 | Element | Composition (%) | 

|---------|-----------------| 

| **Nickel (Ni)** | Balance | 

| **Molybdenum (Mo)** | 23.0-26.0 | 

| **Chromium (Cr)** | 4.5-7.0 | 

| **Iron (Fe)** | 4.0-7.0 | 

| **Cobalt (Co)** | ≤2.5 | 

| **Manganese (Mn)** | ≤1.0 | 

| **Silicon (Si)** | ≤1.0 | 

| **Vanadium (V)** | ≤0.35 | 

| **Carbon (C)** | ≤0.12 | 

| **Phosphorus (P)** | ≤0.04 | 

| **Sulfur (S)** | ≤0.03 | 

2. Physical Properties**

 | Property | Value | 

|----------|-------| 

| **Density** | 9.24 g/cm³ | 

| **Melting Range** | 1330-1380°C | 

| **Thermal Conductivity** | 10.2 W/m·K | 

| **Specific Heat** | 380 J/kg·K | 

| **Coefficient of Thermal Expansion** | 10.8 μm/m·°C | 

| **Modulus of Elasticity** | 190 GPa | 

 **Room Temperature (Annealed Condition):** 

- **Tensile Strength**: 690-825 MPa - 

**Yield Strength (0.2% Offset)**: 310-415 MPa 

- **Elongation**: 40-55% **Elevated Temperature (650°C):**

 - **Tensile Strength**: ~450 MPa - 

**Yield Strength**: ~280 MPa

 --- #### **4. International Standards** 

 | Product Form | Standard | 

|--------------|----------| 

| **Plate, Sheet, Strip** | ASTM B333 | 

| **Bar & Forgings** | ASTM B335 | 

| **Seamless Tubing** | ASTM B622 | 

| **Welding Products** | AWS A5.14 | 

| **Unified Numbering** | UNS N10004 |

 --- #### **5. Applications** 

 **Chemical Processing:**

 - Hydrochloric acid handling equipment 

- Sulfuric acid concentrators 

- Pickling tank components 

- Acid recovery systems 

 **Pharmaceutical Industry:** 

- Reaction vessels 

- Heat exchangers -

 Piping systems handling corrosive media 

 **Pollution Control:** 

- Scrubber systems 

- Waste treatment equipment 

- Flue gas desulfurization components 

 **Other Applications:** 

- Acid production facilities 

- Metal refining equipment 

- Laboratory chemical handling

 --- **Summary**

 Hastelloy W (UNS N10004) provides exceptional corrosion resistance in reducing environments, particularly against hydrochloric and sulfuric acids. Its nickel-molybdenum-chromium composition offers reliable performance in aggressive chemical processing applications. While newer alloys have been developed for some applications, Hastelloy W remains a cost-effective solution for many corrosive chemical environments and continues to be specified in international standards for chemical processing equipment.

Packing of  Hastelloy W (UNS N10004)

Standard Packing: 

Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 1642 gallon liquid totes Special package is available on request.