Powder Metal Valve Seats
Valve Seat Technology Has Changed
Modern engines put much higher levels of thermal and mechanical stress on valve seat inserts. To handle the more severe conditions within this new generation of engines, the OEM is equipping them with high tech sintered valve seats. The normal cast chrome and other alloy iron seats will not adequately withstand the demands of this new engine environment.
Dura-Bond’s patented materials and processing of these powder metal valve seats offer excellent machinability, along with low wear and high heat resistance. These inserts have finely dispersed tungsten carbide residing in a matrix of tempered tool steel and special alloy iron particles to provide all the properties an application requires. Special compositions and processing have been developed to perform in the most extreme duty applications. Complete in-house capabilities, from development and tooling to testing, reduces lead time and cost.
Chemical Composition and Physical Properties
30000 Series Valve Seat Inserts
The 30000 Series is the most machinable of our valve seat materials. it is a sintered valve seat insert which offers a blend of finely dispersed tungsten carbide residing in a matrix of tempered tool steel and special alloy iron particles. The superior machinability is the result of adding our proprietary ingredients and solid dry lubricants to this blend, and by using our special processing techniques during manufacture.
Designed for Unleaded Fuels
This very machinable exhaust seat material is designed for unleaded fuels. The 30000 series is intended for the light to medium duty range. For the heavy or extreme duty use range we recommend our 70000 series valve inserts.
Powder Metal Technology
Dura-Bond has taken full advantage of the new powder metal technology to product a “hard” valve seat which will machine almost like cast iron. The magnified picture will tell the story.
- Powder metal technology allows us to place a special high grade alloy iron (with its natural, tool lubricating graphite rich properties) within a tempered tool steel matrix.
- Because of our special processing, we are able to get very fine, spheroidalized (round shaped), tungsten carbide particles to evenly disperse within the tool steel.
- These sphereoidalized carbides are easier to machine because the tool bit can wedge in-between, with less cutting force and less friction.
- The smaller these “balls” of carbide, the easier it is on your cutting tool, because it will not be hitting any big irregular shaped “iceberg chunks” of carbide.
70000 / 90000 Series Valve Seat Inserts
This is a sintered, high speed (tungsten carbide) tool steel, valve seat insert. This material has special additives blended into the matrix which impart high temperature lubrication properties to the valve seat. These lubrication properties are “built-in” throughout, and are not affected by extreme heat or machining. These solid lubricants enable this material to be used in “dry” fuel applications such as propane (LPG) and natural gas. They prevent the “micro-welding” of the valve seat material to the valve face, therefore eliminating the primary cause of valve seat erosion. They also improve the machinability: Your tools last longer and you can cut faster.
Because of the special high temperature sintering and post heat treat processing, this valve seat material has cermet style metal alloy oxides. this gives it superior wear resistance to both pounding abrasive ware at elevated temperatures. These metal alloy oxides are called “cer-met” style because they are similar to ceramic (they do not soften at elevated temperature), but retain the machinability of metal. It is this high tech, new generation processing that allows us to achieve such high, hot hardness without having to put in massive amounts of expensive alloys, which would be required to achieve equal performance. Normal foundry techniques do not allow this type of structure.
This valve seat insert is, therefore, used in engines using diesel, unleaded gasoline, and propane. We have been setting new longevity records in propane and natural gas applications using this seat.
The micro structure of this valve seat insert is a very fine, evenly dispersed mixture of spheroidal refractory alloy carbides, cermet style metal alloy oxides, and solid lubricant residing in a tempered martensitic matrix.
“Killer Bee” Copper-Infiltrated Valve Seat Inserts
This is a powder metal valve seat with a copper wafer that is infiltrated into the valve seat. This creates a unique product of 15% free copper in the microstructure of the seat. Allowing heat to be quickly transferred and performance greatly improved. GM is equipping the LS3 heads with high tech sintered copper-infiltrated valve seats. High-Performance European engines like BMW and Mercedes also use this technology.
- Offers Superior Thermal Conductivity
- Excellent Machining Characteristics
- High Thermal Expansion
- Lowest Wear – Improved Reliability/Durability
- Superior Surface Finishes
- Suitable for HD Intake and Exhaust Seats, Gas and Diesel
- Compatible with Most Valve Materials
Powder Metal Seat Cutting Videos
Dura-Bond 30000 Series Seat, Venturi Profile, Intake
Dura-Bond 70000 Series Seat, Classic Profile, Exhaust