What is the difference between ACP and ACM panels?

Update:18 Jun 2025

The terms ACP (Aluminum Composite Panel) and ACM (Aluminum Composite Material) are very frequently used interchangeably, to the point where many in the industry consider them synonyms. However, if we're looking for a precise technical distinction, it often comes down to the evolution of the product and, crucially, its core material, especially regarding fire safety.

Here's a detailed explanation in English:
ACP (Aluminum Composite Panel)
Definition: ACP traditionally refers to the finished product, a rigid, flat panel comprising two thin aluminum sheets permanently bonded to a non-aluminum core.
Typical Core: Historically, the most common core material for ACP has been polyethylene (PE). Polyethylene is a thermoplastic polymer, which makes the panel lightweight, flexible, and relatively inexpensive to produce.
Fire Performance: A key characteristic of traditional PE-cored ACP is its combustibility. Polyethylene can melt, drip, and contribute significantly to fire spread, especially in facades of high-rise buildings. This has been a major concern in several well-publicized building fires globally, leading to stricter regulations.
Applications: Due to its light weight, ease of fabrication (cutting, bending, routing), and various finishes, ACP has been widely used for:
Building facades (exterior cladding) for low to mid-rise buildings.
Interior decoration (wall linings, ceilings).
Signage and display boards.
Shop fronts and commercial interiors.
Canopies and column covers.

ACM (Aluminum Composite Material)
Definition: ACM is a broader, more general term that encompasses any composite material made of two aluminum sheets bonded to a core. It can refer to the raw material itself before it is fabricated into specific panel sizes or shapes.
Emphasis on Core Variety & Performance: The term ACM became more prominent as manufacturers developed different core materials to address the fire safety concerns associated with PE-cored ACP. When people speak of "ACM" today, they often imply a product designed to meet higher performance standards, particularly in fire resistance.
Fire-Resistant (FR) Cores: Modern ACM products often feature fire-retardant (FR) mineral-filled cores. These cores are typically a mix of minerals and a small amount of polymer, designed to be significantly less combustible than pure polyethylene. They resist ignition and limit flame spread, achieving higher fire ratings (e.g., Class A2 in European standards, which signifies "non-combustible").
Other Core Types: While FR cores are a major differentiator, ACM can also refer to panels with other core materials like:
Corrugated aluminum core: Offers different mechanical properties.
Aluminum honeycomb core: Provides very high strength-to-weight ratio.
Applications: ACM is increasingly specified for projects requiring superior fire performance and durability, including:
High-rise building facades.
Public buildings (hospitals, schools, airports).
Projects in regions with stringent building codes and fire regulations.
Any application where enhanced safety and performance are critical.

Key Differences Summarized

Feature	ACP (Aluminum Composite Panel)	ACM (Aluminum Composite Material)
Generality of Term	More specific, usually referring to the finished panel.	Broader, encompassing the material itself and its various core types.
Primary Core	Traditionally Polyethylene (PE) core.	Can be PE, but increasingly Fire-Retardant (FR) mineral-filled cores, or other specialized cores.
Fire Resistance	Generally lower fire rating; PE core is combustible.	Higher fire rating (especially with FR cores), designed to meet stricter safety standards.
Cost	Generally less expensive (due to PE core).	Often more expensive (due to advanced, fire-resistant core materials and manufacturing).
Regulatory Compliance	May not meet stringent modern fire safety codes for certain building types/heights.	More likely to comply with the most demanding fire safety regulations.
Perceived Quality	Can be associated with older, less fire-safe products.	Often implies a more advanced, safer, and higher-performance product.