In some examples, an article including a substrate and a multi-layered coating on at least a portion of the substrate. The multi-layered coating including at least one nano-crystalline layer comprising a metal or a metal alloy and a corrosion resistant layer on the at least one nano-crystalline layer. The nano-crystalline layer defining an average grain size of less than 50 nanometers (nm) and the corrosion resistant layer including at least one of nickel metal, tin metal, zinc metal, cadmium metal, chromium metal, nickel-phosphorus alloy, nickel-sulfur alloy, nickel-boron alloy, nickel-cadmium alloy, nickel-zinc alloy, and tin-zinc alloy.

An arc-ablation resistant switch contact and a preparation method thereof is disclosed. The switch contact is a complex having a plurality of layers of layered structure, wherein a first layer is a hydrophobic rubber layer, a second layer is an adhesive layer, a third layer is a sheet metal layer, a fourth layer is an adhesive layer, and a fifth layer is a metal plated layer; wherein, the fifth layer of metal plated layer is formed by dipping a complex of the first layer, the second layer, the third layer and the fourth layer in a chemical plating bath containing refractory metal elements, and depositing on surfaces of the second layer, the third layer and the fourth layer in the complex by a chemical deposition method.

An arc-ablation resistant switch contact and a preparation method thereof is disclosed. The switch contact is a complex having a plurality of layers of layered structure, wherein a first layer is a hydrophobic rubber layer, a second layer is an adhesive layer, a third layer is a sheet metal layer, a fourth layer is an adhesive layer, and a fifth layer is a metal plated layer; wherein, the fifth layer of metal plated layer is formed by dipping a complex of the first layer, the second layer, the third layer and the fourth layer in a chemical plating bath containing refractory metal elements, and depositing on surfaces of the second layer, the third layer and the fourth layer in the complex by a chemical deposition method.

A printed circuit board for a memory card includes an insulating layer; a mounting part on a first surface of the insulating layer, the mounting part being electrically connected to a memory device; and a terminal part on a second surface of the insulating layer, the terminal part being electrically connected to an external electronic appliance, wherein a same metal layer having a same property is formed on exposed surfaces of the mounting part and the terminal part.

A printed circuit board for a memory card includes an insulating layer; a mounting part on a first surface of the insulating layer, the mounting part being electrically connected to a memory device; and a terminal part on a second surface of the insulating layer, the terminal part being electrically connected to an external electronic appliance, wherein a same metal layer having a same property is formed on exposed surfaces of the mounting part and the terminal part.

An arc-ablation resistant switch contact and a preparation method thereof is disclosed. The switch contact is a complex having a plurality of layers of layered structure, wherein a first layer is a hydrophobic rubber layer, a second layer is an adhesive layer, a third layer is a sheet metal layer, a fourth layer is an adhesive layer, and a fifth layer is a metal plated layer; wherein, the fifth layer of metal plated layer is formed by dipping a complex of the first layer, the second layer, the third layer and the fourth layer in a chemical plating bath containing refractory metal elements, and depositing on surfaces of the second layer, the third layer and the fourth layer in the complex by a chemical deposition method.

An arc-ablation resistant switch contact and a preparation method thereof is disclosed. The switch contact is a complex having a plurality of layers of layered structure, wherein a first layer is a hydrophobic rubber layer, a second layer is an adhesive layer, a third layer is a sheet metal layer, a fourth layer is an adhesive layer, and a fifth layer is a metal plated layer; wherein, the fifth layer of metal plated layer is formed by dipping a complex of the first layer, the second layer, the third layer and the fourth layer in a chemical plating bath containing refractory metal elements, and depositing on surfaces of the second layer, the third layer and the fourth layer in the complex by a chemical deposition method.