Disclosed are pretreatment compositions and associated methods for treating metal substrates with pretreatment compositions, including ferrous substrates, such as cold rolled steel and electrogalvanized steel. The pretreatment composition includes: a Group IIIB and/or IVB metal; free fluoride; and molybdenum. The methods include contacting the metal substrates with the pretreatment composition.

Disclosed are pretreatment compositions and associated methods for treating metal substrates with pretreatment compositions, including ferrous substrates, such as cold rolled steel and electrogalvanized steel. The pretreatment composition includes: a Group IIIB and/or IVB metal; free fluoride; and molybdenum. The methods include contacting the metal substrates with the pretreatment composition.

The present disclosure relates to a method of chemical pretreatment and selective phosphation of a composite metal construction comprising at least a portion made of aluminum and at least a portion made of zinc and optionally a further portion made of iron, which includes (I) treating the composite metal construction with an aqueous zinc phosphation composition that results in the formation of a surface-covering crystalline zinc phosphate layer and thenwith an intervening water rinse operation (II) applying an aqueous acidic passivation composition,

The present disclosure also relates to a corresponding zinc phosphation composition, to a concentrate for production thereof, to a corresponding composite metal construction and to a method of using thereof.

The present disclosure relates to a method of chemical pretreatment and selective phosphation of a composite metal construction comprising at least a portion made of aluminum and at least a portion made of zinc and optionally a further portion made of iron, which includes (I) treating the composite metal construction with an aqueous zinc phosphation composition that results in the formation of a surface-covering crystalline zinc phosphate layer and thenwith an intervening water rinse operation (II) applying an aqueous acidic passivation composition,

The present disclosure also relates to a corresponding zinc phosphation composition, to a concentrate for production thereof, to a corresponding composite metal construction and to a method of using thereof.

Disclosed is a system for treating a substrate surface. The system includes a conditioner composition and a first pretreatment composition. The conditioner composition comprises a hydroxide source and the first pretreatment composition comprises a magnesium element, a halide element, and an oxidizing agent. Methods of treating a substrate surface using the conditioner composition and the first pretreatment composition also are disclosed. Also disclosed are substrates treated with the system and method.

Disclosed is a system for treating a substrate surface. The system includes a conditioner composition and a first pretreatment composition. The conditioner composition comprises a hydroxide source and the first pretreatment composition comprises a magnesium element, a halide element, and an oxidizing agent. Methods of treating a substrate surface using the conditioner composition and the first pretreatment composition also are disclosed. Also disclosed are substrates treated with the system and method.

Disclosed herein is a first composition comprising a trivalent chromium cation and an aqueous carrier. Also disclosed herein is a second composition comprising a permanganate anion and an aqueous carrier. Also disclosed herein is a system for treating a metal substrate comprising a first composition comprising a trivalent chromium cation and an aqueous carrier and optionally a second composition comprising a permanganate anion and an aqueous carrier. Also disclosed herein is a method of treating a metal substrate comprising contacting at least a portion of the substrate surface with a first composition comprising a trivalent chromium cation and an aqueous carrier and optionally contacting at least a portion of the substrate surface with a second composition comprising a permanganate anion and an aqueous carrier.

Disclosed herein is a first composition comprising a trivalent chromium cation and an aqueous carrier. Also disclosed herein is a second composition comprising a permanganate anion and an aqueous carrier. Also disclosed herein is a system for treating a metal substrate comprising a first composition comprising a trivalent chromium cation and an aqueous carrier and optionally a second composition comprising a permanganate anion and an aqueous carrier. Also disclosed herein is a method of treating a metal substrate comprising contacting at least a portion of the substrate surface with a first composition comprising a trivalent chromium cation and an aqueous carrier and optionally contacting at least a portion of the substrate surface with a second composition comprising a permanganate anion and an aqueous carrier.

A magnesium alloy layered composite for an electronic device can include a magnesium alloy substrate, a passivation layer positioned on the magnesium alloy substrate, and a sol-gel layer positioned on the passivation layer. The passivation layer can include a molybdate, a vanadate, a phosphate, a chromate, a stannate, or a manganese salt. The sol-gel layer can include a silicate, a silane, a siloxane, or a metal C1-C5 alkoxide.

A system having a removable electronic component employs an abrasion-resistant thermally conductive film as a thermal interface between the removable electronic component and a heat sink. The abrasion-resistant film reduces thermal impedance between the removable electronic component and the heat sink when the removable electronic component is repeatedly installed and removed from a chamber in a host device. The abrasion-resistant film includes a polymer formed from a silicone-containing resin and an inorganic particulate filler; the film may also be interlocked with a corrosion protection layer at the heat sink. A method of forming a heat sink is provided that minimizes increases in thermal impedance.