Volvo STD 5742-104 Phosphating Y 104

The “Volvo STD 5742-104 Phosphating Y 104” standard, developed by Volvo, covers the phosphating of iron, steel, electro-zinc coated steel plate, hot-dip galvanized steel plate, aluminum, and galvanized steel plate. It also includes the phosphating of iron and steel in conjunction with rust-preventive oil for corrosion protection, protection during break-in with lubricants, and phosphating of the flank surfaces of gear teeth. This standard is also applicable to gear parts with friction requirements.

Phosphated surfaces should be matte and not polycrystalline. They must be free from uncoated areas, flaking and irregular deposits, as well as process chemical residues that could cause corrosion.

The mass of the phosphate coating must conform to the requirements specified in the table provided within the standard. Coating mass refers to the unlubricated phosphate coating and can be determined according to Volvo STD 5714-105. Where the coating mass is not specified, it should be determined according to the specified corrosion resistance requirement and, in some cases, friction.

According to Volvo STD 423-0010 standard, after testing, the coating must meet the corrosion resistance requirements specified in the table.

Y 104-2 (zinc or manganese phosphating and oil application for protection during transport and storage) must be coated with an anti-corrosion agent in accordance with Volvo STD 121-0009 standard after the phosphating process.

For Y 104-1 (zinc phosphating as a base material for paint), testing of the paint properties specified in the relevant standard is also required. An example of such a standard is Volvo STD 1281-21 Electroplating paint (EC paint).

The applications of this standard are as follows:

• Y 104-1 Zinc phosphating as a paint base.
• Y 104-2 Zinc or manganese phosphating and lubrication for protection during transport and storage. Also designed for friction requirements in threaded fasteners.
• Y 104-3 Manganese phosphating for protection during initial use.
• Y 104-4 Manganese phosphating and lubrication application for protection during initial use where severe wear is expected.
• Y 104-5 Phosphating in a specific process for parts and threaded fasteners whose functionality depends on certain fixed functions (e.g., torque-voltage relationship). This class includes screws fitted to very high-stress connections, such as motor screws and yield-point tightened screws.
• Y 104-6 Manganese phosphating for the protection of the tooth flank during initial use. Can also be prescribed for other surfaces with similar requirements.

This standard covers brands such as Volvo trucks, Volvo construction equipment, and others – but does not apply to Volvo cars. Volvo maintains a comprehensive set of corporate standards to ensure quality, consistency, and environmental compliance across its supply chain. Among these is the Volvo STD 5742-104 standard, a technical specification dedicated to phosphating processes, focusing specifically on the Y 104 variant. This standard defines the requirements for phosphating surface treatments applied to steel components, particularly threaded fasteners and other metal parts.

Phosphating is a chemical conversion coating process that increases corrosion resistance, improves paint adhesion, and provides lubricating properties for metal surfaces. The Y 104 designation refers to a specific class or type in Volvo's phosphating system and typically involves combining manganese phosphating with lubrication.

The key features addressed in the Volvo STD 5742-104 standard are as follows:

• Coating type: Manganese phosphating (typically specified for deep-drawn steel sheets, galvanized surfaces, or threaded fasteners).
• Appearance: Gray-black color after phosphating and lubrication.
• Corrosion resistance: Resistance to red rust is required in specific tests, with minor pitting permitted.
• Coating weight: Minimum/maximum weights specified to ensure performance are indicated (e.g., g/m²).
• Friction characteristics: The standard for threaded fasteners defines target friction coefficients during assembly (e.g., target value 0,11 plus/minus tolerance range). These values ​​are tested according to the relevant Volvo STD 5511-72 standard. This ensures consistent torque-stress behavior during bolting.
• Mechanical requirements: This applies to threaded fittings where a specific preloading requirement is not given in the design document.
• Environmental compliance: There are strict rules regarding the chemicals used, and substances on Volvo's red list are prohibited (Volvo STD 100-0005 standard). All products must pass Volvo's internal health and environmental assessment.

For Volvo Group suppliers, compliance with the Volvo STD 5742-104 standard is legally binding when referenced in contracts, drawings, or purchase orders. This ensures:

• Reliable corrosion protection for components exposed to harsh environments (e.g., trucks, buses, construction equipment).
• Consistent assembly performance (critical for safety-related fasteners).
• Environmental responsibility through the restriction of hazardous substances.
• Compliance with other Volvo standards (e.g., friction testing, material lists).

In conclusion, the Volvo STD 5742-104 standard is a specific yet fundamental standard within the Volvo Group ecosystem, focusing on high-performance manganese phosphating for steel parts. It balances functional performance (corrosion protection and friction control) with environmental responsibility, a hallmark of modern automotive and heavy-duty engineering.

For many years, our organization, with its competent and experienced staff, has been understanding the needs of its customers, providing the advanced testing services they require, and assisting them in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services in accordance with the Volvo STD 5742-104 standard.