CNC brass parts stand out as indispensable components in electronics, automotive, medical, and luxury manufacturing, leveraging brass’s inherent advantages—excellent conductivity, corrosion resistance, and machinability—paired with CNC’s high precision. From micro-connector pins to custom automotive fittings, these parts balance functional performance and aesthetic appeal, making them a top choice for demanding applications. Below is a detailed breakdown of their material properties, machining processes, and end-to-end customization.
CNC Brass Parts: Precision Machining and Industry-Specific Solutions

Ⅰ.Core Brass Material Properties & Advantages

Brass alloys vary in composition to suit different needs; the table below highlights the most widely used grades for CNC machining:
Brass Grade
Density (g/cm³)
Tensile Strength (MPa)
Hardness (HV)
Conductivity (IACS%)
Salt Spray Resistance (h)
Core Advantages
Typical Certifications
H65
8.40
390
100
28
≥800 (nickel-plated)
Easy machining, cost-effective
EN 12164
H70
8.50
410
120
26
≥1000 (gold-plated)
High gloss, low stress corrosion
ASTM B134
HPb59-1
8.50
420
130
24
≥600
Self-lubricating, ideal for complex shapes
RoHS
HSn62-1
8.45
380
110
22
≥1200
Seawater resistance, wear-resistant
ISO 4274-1

Customization Core Requirements

  1. Precision Demands: Dimensional tolerance as tight as ±0.005mm (e.g., aerospace connectors), surface roughness Ra≤0.2μm for mirror-finish parts.
  1. Functional Needs: Electrical contact resistance ≤5mΩ (electronic components), pressure resistance ≥10MPa (hydraulic fittings).
  1. Environmental Adaptability: Neutral salt spray test ≥720h (outdoor hardware), stable performance at -40℃~120℃ (automotive parts).

II.Key CNC Machining Technologies for Brass

1. CNC Turning & Milling

  • Advantages: 5-axis CNC systems achieve one-step machining of complex geometries (e.g., spiral grooves, eccentric shafts) with accuracy ±0.003mm. For micro-parts (diameter ≥0.5mm, like watch pins), spindle speeds reach 8000-12000rpm.
  • Process Parameters: Feed rate 0.05-0.3mm/r, cutting fluid (water-soluble type) to reduce thermal deformation (≤0.003mm).

2. Surface Treatment

Process
Application
Technical Highlights
Gold/Silver Plating
Electronic connectors
Plating thickness 0.1-3μm, contact resistance reduced by 30%
Mirror Polishing
Luxury decor
Ra≤0.1μm, glossiness ≥90GU
Passivation
Medical parts
Chromium-free film (2-5μm), compliant with ISO 13485

3. Quality Inspection

  • Precision Testing: Coordinate Measuring Machine (CMM) checks geometric tolerances (roundness ≤0.002mm, perpendicularity ≤0.005mm).
  • Functional Testing: Tensile tests (yield strength ≥200MPa), helium leak detection (leakage ≤1×10⁻⁹ mbar·L/s for sealed parts).

Ⅲ.End-to-End Customization Process

1. Design & Material Selection

  • Structural Optimization: Use FEA (ANSYS) to simulate stress distribution—e.g., optimizing stepped shaft fillets (R≥0.5mm) to extend fatigue life by 40%.
  • Material Matching:
    • Electronics: H70 brass (high conductivity) + gold plating for connectors.
    • Marine: HSn62-1 (seawater resistance) for shipboard fittings.

2. Production & Delivery

  • Rapid Prototyping: 3D-printed brass samples in 24h, CNC first-piece machining in 3 days.
  • Mass Production: Automated lines (truss robots) achieve 5000pcs/day for standard parts, with 20% faster delivery via smart scheduling.

3. Quality Assurance

  • Tests: Neutral salt spray (≥720h), 冷热循环 (-40℃~80℃, 50 cycles), and wear resistance (≤0.005mm/1000h).
  • Certifications: ISO 9001, RoHS, REACH—meeting global market standards.

Ⅳ.Typical Application Scenarios

  1. Electronics: H70 brass connector pins (CNC turned, gold-plated 3μm) with insertion loss ≤0.1dB (10GHz), adapt to high-density PCBs.
  1. Automotive: HSn62-1 fuel line connectors (CNC milled) with pressure resistance ≥15MPa, resist gasoline corrosion (volume change ≤2%).
  1. Medical: HPb59-1 surgical instrument shafts (passivated, Ra≤0.4μm) compliant with USP Class VI, ensure sterilization safety.
  1. Luxury Goods: H65 brass watch crowns (mirror-polished, rose gold-plated 2μm) with 0.05mm-deep LOGO engraving (accuracy ±0.01mm).

Ⅴ.Technology Selection Guide

Requirement Type
Preferred Tech Combination
Brass Grade
Core Indicators
Delivery Cycle
Ultra-Precision Electronics
5-axis CNC + Gold Plating
H70
±0.005mm, ≤3mΩ
5 days (proto), 25 days (mass)
Marine Corrosion-Resistant
CNC Milling + Passivation
HSn62-1
≥1200h salt spray
7 days (proto), 30 days (mass)
Luxury Decor
Precision Turning + Polishing
H65
≥90GU glossiness
6 days (proto), 28 days (mass)
For over 26 years, Xiamen Goldcattle (a national high-tech enterprise) has specialized in CNC brass parts, equipped with 5-axis CNC machines (tolerance ±0.005mm) and full surface treatment capabilities. Our solutions cover prototyping to mass production, with certifications including ISO 9001 and RoHS. Whether you need custom electronic pins or luxury hardware, we tailor processes to your drawings/samples.
To explore our precision machining capabilities and request a quote, visit: https://www.xmgoldcattle.com/

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