Nissan, Japan, has adopted valve seats manufactured using cold spray technology, marking a world-first application in automotive engines.
Cold spray technology is now being applied by Nissan to its new 1.5-liter turbocharged engine, which is exclusively designed for power generation within the third-generation e-POWER hybrid powertrain.
The first vehicle globally to feature this new e-POWER system is the Qashqai compact crossover, which began production at Nissan’s state-of-the-art factory in Sunderland, UK in July.
The new 1.5-liter turbocharged engine (codename ZR15DDTe) employs Nissan’s proprietary STARC concept, which elevates thermal efficiency to 42% by stabilizing in-cylinder combustion.
A key element of the STARC concept is minimizing airflow turbulence from the intake port into the combustion chamber, thereby generating a strong tumble flow.
In conventional engines, the design of the intake port is constrained by the necessity for press-fitted, sintered valve seats, which limit the ability to optimize port shape for ideal tumble flow.
Nissan engineers addressed this challenge by developing a novel valve seat using cold spray technology. This process allows a coating to be directly formed onto the cylinder head surface, eliminating the need for a separate valve seat component and enabling the creation of an optimized intake port geometry. Furthermore, compared to similar methods, its higher thermal conductivity enables improved cooling performance around the valves.
The new valve seat is produced by spraying dissimilar metal powders at supersonic speed onto the aluminum alloy cylinder head surface, forming a robust and durable coating that adheres strongly without melting the base material.
Cold spray technology operates below the melting points of the materials involved, enabling the bonding of dissimilar metals without melting. This process prevents the formation of excessive intermetallic compounds and micro-voids (porosity) that are common in traditional fusion welding methods. As a result, cold spray coatings exhibit superior adhesion, durability, and reliability—crucial qualities for engine valve seats.
This application represents a world-first in automotive engines and leverages Nissan’s extensive expertise in powertrain design, materials engineering, and manufacturing. The process incorporates a specially developed cobalt-free, copper-based alloy with excellent thermal conductivity, in-house nozzles inspired by polishing techniques used in forged mold production, and AI-driven quality assurance systems.
These innovations reflect years of accumulated know-how, enabling the successful implementation of cold spray technology in engine valve seats.
Image – New ZR15DDTe engine cylinder head.
For more information:
Nissan Motor Corporation
https://www.nissan-global.com/EN/
