For general hot and corrosion-prone threaded assemblies in steel and cast iron where no specification rules it out: manifold studs, pipe threads, machine bolting, wheel hardware and workshop use generally. It avoids the galvanic problem copper has with stainless and aluminium, and costs considerably less than nickel. If you stock a single anti-seize for mixed work, this is normally the one to hold, with a metal-free product alongside for food and inspection-critical jobs.

Aluminium sits between the two. Its ceiling of roughly 900 to 1,100 °C is below nickel's, and its load capacity is generally lower, but it avoids copper's galvanic incompatibility with stainless and aluminium and costs far less than nickel. Copper remains common on hot steel exhaust and brake hardware; nickel is specified where copper is banned or temperatures are extreme. Aluminium covers the broad middle where neither constraint applies.

Many products are built on an aluminium complex grease and offer good resistance to salt water, which makes them a common choice for carbon steel deck hardware, fittings and fasteners in marine and offshore work. Check the specific product's water washout and salt spray data rather than assuming. Where stainless is involved, confirm the product is genuinely copper-free, since some compounds sold as general purpose contain copper as well as aluminium.

Yes. This applies to every anti-seize and is the most frequent cause of damage attributed to these products. Lubricating the threads reduces friction, so more of the applied torque converts into bolt tension, and a fastener tightened to its dry figure can be over-tensioned to the point of yielding or breaking. Use the reduction factor stated by the fastener or compound manufacturer for the specific product in use.

Yes. Unlike copper compounds, an aluminium-based product does not form an aggressive galvanic couple with aluminium components, which is one of the reasons it is preferred for mixed workshop use. It is commonly applied to aluminium housings, manifolds and castings that must be separated later. As always, keep it out of blind holes in quantity, since trapped compound is effectively incompressible and can crack a light alloy casting.

A thin, even film on the male thread. Excess is squeezed from the joint on assembly, collects dirt and grit, and contaminates surrounding surfaces without improving the result. Keep it off brake friction surfaces, electrical contact faces and anything that will later be painted. On studs, coating the engaged length is sufficient; there is no benefit in filling the nut or packing the hole.

Wear gloves and eye protection: these compounds are persistent, stain heavily and are unpleasant to remove from skin. Keep the container closed so the carrier does not dry and the solids do not settle out, and stir if separation has occurred. Store out of direct sun and away from temperature extremes. Keep a dedicated brush with each tin, because sharing brushes cross-contaminates compounds and can defeat a deliberate copper-free or metal-free specification.