Tin-Coated Iron Sliding Component With Exposed Graphite

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing sliding components with solid lubricant particles in the surface layer face issues of particle loss leading to unstable friction coefficients and poor sliding characteristics.

Innovation Solution

A sliding component with an iron substrate containing graphite particles and a tin coating that exposes graphite through the tin layer, enhancing stable sliding characteristics by retaining graphite particles during use.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If solid lubricant particles are embedded in the surface layer, then wear resistance is improved, but the particles may fall off during sliding leading to unstable friction characteristics

Engineering Contradiction:
Improvewear resistanceVSAvoidstability of friction characteristics
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent introduces an intermediate layer composed of metal powder particles (such as copper, nickel, or zinc) between the substrate and the solid lubricant particles. This intermediate layer acts as a mediator that securely holds the solid lubricant particles while allowing them to function effectively, preventing particle detachment during sliding and ensuring stable friction characteristics throughout the component's service life.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If a tin coating is applied to retain graphite particles, then sliding characteristics are improved, but the coating process complexity increases

Engineering Contradiction:
Improvesliding characteristicsVSAvoidcoating process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs parameter changes by carefully controlling the thickness of the tin coating layer. The tin coating is applied with a specific thickness range (typically 5-50 μm) that is sufficient to retain graphite particles and provide corrosion resistance, yet thin enough to allow graphite particles to be exposed or near-exposed at the surface. This parameter optimization achieves improved sliding characteristics through a relatively simple coating process without excessive complexity.

Inventive Principle:
Principle #35Parameter changes

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

The component achieves a low friction coefficient and stable sliding performance from the initial stage, with the tin coating retaining graphite particles and reducing friction fluctuations.

Implementation Method 1

a tin coating on the iron substrate, the tin coating including tin as a main material

Methodology Applied
Scientific EffectAdhesion: Adhesive

Implementation Method 2

The graphite particles are exposed through the tin coating

Methodology Applied
Scientific EffectSolid lubrication: Lubrication

Data Source

PatentEP4043748B1Sliding component and method for manufacturing same
Publication Date: 2025.08.27 HITACHI CONSTRUCTION MACHINERY CO LTD
  • EP4043748B1 patent drawingFigure 1~2
  • EP4043748B1 patent drawingFigure 3~4
  • EP4043748B1 patent drawingFigure 5~6

AI summary

Provided is a sliding component having a low coefficient of friction and capable of exerting stable sliding characteristics from the initial stage of sliding, and a manufacturing method capable of easily manufacturing the sliding component. A sliding component (1) includes an iron substrate (10), in which graphite particles (13) are dispersed in an iron base (11), and a tin coating (20) formed on the iron substrate (10), the tin coating (20) including tin as a main material. The graphite particles (13) of the sliding component (1) are exposed through the tin coating (20). The manufacturing method includes: a preparation step of preparing an iron substrate (10) including graphite particles (13) dispersed in an iron base (11); and a film forming step of forming a tin coating (20) on the surface of the iron substrate (10), the tin coating (20) including tin as a main material. The film forming step forms the tin coating (20) so that the graphite particles (13) are exposed through the tin coating (20).