Pure Tin (Sn)

Pure Tin (Sn) is a soft, silvery-white post-transition metal known for excellent corrosion resistance, high ductility, and good electrical conductivity. It has been used for over 5,000 years and remains essential in electronics, soldering, coatings, food packaging, and chemical applications.

Basic Material Information

Strengthening & Metallurgical Behavior

Pure tin is not heat-treatable. Strengthening is limited to grain refinement or minor alloying (Sn-Sb, Sn-Cu, Sn-Ag systems).

Allotropic Transformation (Tin Pest):
Below 13.2 °C, metallic β-tin can transform into brittle α-tin, causing volume expansion. This is prevented by controlled purity, alloying (Sb, Bi), and modern processing methods.

Corrosion & Chemical Resistance

Pure tin exhibits excellent corrosion resistance in:

✔ Water and atmospheric environments
✔ Organic acids
✔ Food & beverage contact applications

Vulnerable to strong acids, alkalis, and high-temperature oxidation. A thin, stable SnO₂ oxide layer provides protection and is non-toxic.

Refining & Processing Properties

Refining: Pyrometallurgical smelting (from cassiterite), electrolytic refining, vacuum refining for electronic-grade tin.

Processing: Excellent castability, very low melting temperature, easily rolled, extruded, electroplated. Poor load-bearing capability.

Available Forms

Ingots, bars, rods, sheets, foils, powder, granules, pellets, wire, electroplating anodes.

Key Characteristics

✔ Extremely ductile and malleable
✔ Excellent corrosion resistance
✔ Non-toxic and food-safe
✔ Low melting point
✔ Easily alloyed and electroplated

Applications

🔌 Electronics: lead-free solders, wire plating, semiconductor coatings
🥫 Packaging: tinplate for food cans
🧪 Chemical industry: corrosion-resistant linings
⚙️ Metallurgy: bronze, babbitt metals, pewter
🏥 Medical & laboratory packaging

Advantages

✔ Excellent corrosion resistance
✔ Low-temperature melting for soldering
✔ Non-toxic alternative to lead
✔ Easy processing & electroplating
✔ Superior surface finish

Limitations

⚠ Very low mechanical strength
⚠ Tin whisker formation risk in electronics
⚠ Tin pest at low temperatures
⚠ Poor high-temperature performance

Metal Comparison

Summary:
Pure Tin (Sn) is a corrosion-resistant, low-melting, non-toxic metal essential to electronics, food packaging, soldering, and alloy systems. While it lacks structural strength, its processing ease, chemical stability, and electrical properties make it indispensable in modern industry.