Built to Resist Rust: How NEXALUME® Fights Corrosion
Corrosion is the single greatest enemy of steel in tropical Indonesia — where heat, humidity, salt-laden coastal air and industrial pollution work together to attack unprotected metal. NEXALUME®, the 55% Aluminium-Zinc coated steel by PT Tata Metal Lestari, is engineered specifically to hold that attack at bay. It is a core part of the company's guiding vision: a World Without Rust.
A 55% Aluminium-Zinc Coating
NEXALUME® is a hot-dip 55% Aluminium-Zinc (Al-Zn) coated steel, produced on a Continuous Galvanizing Line using dual-pot technology. The result is a distinctive spangled surface and maximum corrosion protection built directly into the coil. In export markets the product is designated "Prime Hot Dip 55PCT Al-Zn Alloy Coated Steel Sheet."
The reason the Aluminium-Zinc combination is so effective lies in how the two metals protect the steel through two complementary mechanisms working at once:
- Barrier protection — the aluminium-rich region of the coating forms a stable, durable layer that physically seals the steel away from moisture, oxygen and airborne contaminants.
- Sacrificial protection — the zinc-rich region corrodes preferentially (galvanically) at cut edges and scratches, protecting the exposed steel underneath even where the coating has been broken.
Barrier protection gives the coating its long service life; sacrificial protection guards the vulnerable spots that a purely inert coating would leave unprotected. Together they make NEXALUME® well suited to Indonesia's demanding tropical climate.
Coating Mass and Grades
Corrosion performance scales with how much coating is applied. NEXALUME® is available in coating masses of AZ150 and AZ200 (150–200 g/m²) — with the full galvalume range spanning AZ50 through AZ200 per JIS G3321 — so the specification can be matched to the severity of the environment.
The product covers a wide range of steel grades — G250, G300, G350, G450, G500 and G550 — in Base Metal Thickness from 0.25 mm to 2.50 mm and widths of 600–1250 mm, giving designers flexibility from light roofing sheet to structural sections.
Certified to International Standards
NEXALUME® is manufactured to AS/NZS 1365 and AS/NZS 1397, and is equivalent to JIS G3321, ASTM A792/A792M, SNI 4096:2007 and MS 1196:2020. PT Tata Metal Lestari operates under ISO 9001 and ISO 14001 management systems, is an ASTM International member, and its products are exported to more than 20 countries — assurance that the corrosion protection you specify is the corrosion protection you receive.
Where It Is Used
Its combination of formability and corrosion resistance makes NEXALUME® ideal for roofing, wall cladding and structural applications, as well as roll-forming and press-stamping in construction. It also serves as the substrate for NEXCOLOR®, Tata Metal's pre-painted steel — meaning the same Aluminium-Zinc corrosion defence sits beneath every coloured NEXCOLOR® panel.
Verifying Authenticity
Genuine NEXALUME® coils carry clear branding printed along the strip, including the coating and grade designation (for example NEXALUME® AZ100 G550 BMT 0.40) and the Indonesian standard mark SNI 4096-2007 LSPr-011-IDN. Always check for these markings to be sure you are getting authentic, standard-compliant corrosion protection.
