Composite Cylinder Head via Intermediate Layer

Solution Overview

Problem

Cylinder heads for internal combustion engines face challenges in meeting stringent mechanical and thermal load requirements due to limitations in casting alloys, where high-strength alloys are difficult to cast and conventional alloys fail to withstand increasing combustion pressures and temperatures.

Innovation Solution

A cylinder head is designed with two prefabricated sections, one made from a high-strength but poorly castable alloy for resilience and the other from a well-castable alloy for complex shape, connected via an intermediate layer of a suitable metallic material like AlZn, allowing for separate optimization of mechanical and thermal properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If high-strength alloys are used to improve mechanical load capacity, then strength increases, but castability deteriorates making it difficult to produce complex shapes

Engineering Contradiction:

Improvemechanical load capacityVSAvoidcastability

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The cylinder head is divided into multiple sections (combustion chamber side and counterweight side) that can be cast separately using different alloys optimized for their specific functional requirements, then joined together through soldering or brazing. This segmentation allows each section to be manufactured with the most suitable material properties for its intended use.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the cylinder head are assigned different material qualities - the combustion chamber side uses high-strength alloy for mechanical resilience, while the counterweight side uses well-castable alloy for complex shape reproduction. This local differentiation of material properties optimizes both strength and castability in their respective locations.

Inventive Principle:

Principle #3Local quality

2Ease of manufacture

If well-castable light metal alloys are used to achieve good reproduction of complex shapes, then castability improves, but mechanical strength decreases making it insufficient for high combustion pressures

Engineering Contradiction:

ImprovecastabilityVSAvoidmechanical strength

Core Design Contradiction:

Ease of manufactureVSStrength

Solution Approach 1:

The cylinder head is divided into multiple sections (combustion chamber side and counterweight side) that can be cast separately using different alloys optimized for their specific functional requirements, then joined together through soldering or brazing. This segmentation allows each section to be manufactured with the most suitable material properties for its intended use.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the cylinder head are assigned different material qualities - the combustion chamber side uses high-strength alloy for mechanical resilience, while the counterweight side uses well-castable alloy for complex shape reproduction. This local differentiation of material properties optimizes both strength and castability in their respective locations.

Inventive Principle:

Principle #3Local quality

3Productivity

If conventional casting processes are used to produce cylinder heads in large quantities, then productivity increases, but the ability to meet increasing mechanical and thermal load requirements deteriorates

Engineering Contradiction:

Improveproduction quantityVSAvoidload capacity

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The cylinder head is divided into multiple sections (combustion chamber side and counterweight side) that can be cast separately using different alloys optimized for their specific functional requirements, then joined together through soldering or brazing. This segmentation allows each section to be manufactured with the most suitable material properties for its intended use.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The cylinder head is constructed as a composite structure combining different metal alloys in specific sections. The combustion chamber side uses high-strength alloy for mechanical resilience, while the counterweight side uses well-castable alloy for complex shape reproduction. This composite approach allows the final product to exhibit both high strength and good castability characteristics.

Inventive Principle:

Principle #40Composite materials

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enables the production of cylinder heads with enhanced load capacity and complex shapes, ensuring optimal performance and durability under high mechanical and thermal stresses while maintaining economical large-scale production.

Implementation Method 1

the two sections are prefabricated in separate work steps and then firmly and inseparably connected to one another by an intermediate layer in the manner of a soldered connection

Methodology Applied

Scientific EffectSoldering: Soldering

Data Source

PatentEP1803520B1Cylinder head made out of at least two precast sections and method for its manufacture

Publication Date: 2017.08.02 NEMAK LINZ

Figure 1
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Figure 3

AI summary

Cylinder head (1) comprises two sections (2, 3) joined together via a metallic intermediate layer (4) which extends between the sections. An independent claim is also included for a method for the production of a cylinder head. Preferred Features: The metallic intermediate layer melts at a melting temperature which is higher than the operating temperature for the cylinder head and lower than the melting temperature of the cast materials used for making the sections.