What files do you need to evaluate a PCBA project?

Send Gerber files (RS-274X or ODB++), a BOM with manufacturer part numbers, the pick-and-place (centroid) file and an assembly drawing. If you need functional testing, add the test specification, firmware and any test fixture requirements so FCT can be planned before production.

Do you support low-volume prototypes as well as mass production?

Yes. The same SMT lines handle engineering prototypes, pilot runs and volume production. Small batches carry a higher unit cost because stencil, line setup and component reel minimums are spread across fewer boards; our engineers advise on panelization and alternate parts to reduce that cost.

How do you control PCBA quality?

Quality is controlled in a closed loop: incoming material inspection, 3D SPI after solder paste printing, AOI after reflow, X-ray inspection for BGA and hidden joints, and functional testing before packing. Workmanship follows IPC-A-610 Class 2 by default, with Class 3 available on request, and the process targets a first-pass yield of 98.5% or higher.

Can you source the electronic components for us?

Yes. We offer full turnkey service where we procure all components through long-term supply partners, partial turnkey where you consign critical parts, and consignment assembly where you supply all materials.

Can overseas buyers audit the factory before ordering?

Yes. Buyers can schedule an on-site audit at our Shenzhen facility or a live video audit covering material storage, SMT lines, inspection stations and traceability records.

Best Electrolytic Hard Gold Manufacturers & Service

Precision Turnkey PCBA Solutions & Finished Assemblies

Explore our active manufacturing lines featuring automated SMT, selective electrolytic plating, and turnkey hardware production.

Engineering Depth: Electrolytic Hard Gold in Global Electronics

Why modern mission-critical hardware demands galvanically deposited hard gold over immersion finishes like ENIG or ENEPIG.

Alloy Hardening Dynamics

Unlike immersion gold (soft Au 99.9% purity, Knoop 60–90), electrolytic hard gold introduces cobalt or nickel dopants (0.1–0.3%) into the crystal lattice, boosting Knoop hardness to 130–200 HK. This prevents mechanical galling during continuous edge-card insertion cycles.

Diffusion Barrier Architecture

We electroplate an electrolytic low-stress sulfamate nickel barrier (typically 100 to 200 microinches) beneath the hard gold layer. This completely prevents copper migration, thermal atom diffusion, and premature contact resistance spikes across thermal operating extremes.

Corrosion & Tribology Control

Compliant with MIL-DTL-45204 Type II, Grade C, electrolytic hard gold provides exceptional tribological protection against fretting corrosion, chemical oxidation, and high-frequency friction wear encountered in automotive and industrial control electronics.

Technical Specification Matrix: Hard Gold vs. Alternate Finishes

A data-backed comparative analysis for procurement specialists, hardware architects, and component engineers.

Surface Finish Type	Hardness (Knoop HK)	Plating Thickness Range	Insertion Cycle Endurance	Solderability Performance	Primary Industrial Use Case
Electrolytic Hard Gold (Au-Co/Ni)	130 – 200 HK	15 to 50 μin (0.38 – 1.27 μm)	> 20,000+ Cycles	Poor (Requires Selective Mask)	PCIe Fingers, Edge Connectors, Keypads
ENIG (Electroless Ni / Immersion Au)	60 – 90 HK	1 to 3 μin (0.025 – 0.075 μm)	< 100 Cycles	Exceptional (SMT & BGA)	Fine-pitch planar IC pads, Dense SMT
Electrolytic Soft Gold (Pure 99.99%)	50 – 80 HK	10 to 40 μin (0.25 – 1.0 μm)	< 50 Cycles	Excellent for Wire Bonding	COB (Chip-on-Board), Ultrasonic Wire Bonding
ENEPIG	80 – 120 HK	Au: 1–2 μin / Pd: 2–4 μin	< 200 Cycles	Universal (Solder + Wire Bond)	High-density packaging, Aerospace arrays
Immersion Silver (IAg)	40 – 60 HK	6 to 16 μin (0.15 – 0.40 μm)	< 20 Cycles	Good (Short shelf life)	High-frequency RF, Membrane switches

Chinese Manufacturing Ecosystem & Efficiency Advantages

Leveraging Shenzhen's localized industrial supply chain to compress hard gold turnaround times while slashing overall procurement expenditures.

Shenzhen Turnaround Velocity

Located in the heart of Longgang, Shenzhen, our plating facility achieves 24-hour rapid prototyping for selective hard gold busbar circuits and fast multi-panel scaling, bypassing the week-long queue times common in Western boutique facilities.

Integrated Busbar & SMT Lines

By uniting electrochemical bath plating lines, tie-bar beveling (20°, 30°, 45° edge beveling), and automated SMT assembly under one roof, we eliminate multi-vendor handoff scrap and protect against intermetallic contamination.

Precious Metal Yield Optimization

Our proprietary dry film selective masking and automated current density rectifiers ensure precise gold deposition down to ±1.5 microinches, eliminating precious metal waste and transferring massive BOM cost savings to high-volume contracts.

20+

Years SMT & Plating Experience

800+

Global Enterprise Accounts

1.2M+

Daily SMT Placement Points

98.5%

Verified First-Pass Assembly Yield

High-Reliability Industrial Application Scenarios

Where mechanical cycling, environmental humidity, and electrical contact resistance cannot afford a single point of failure.

PCIe & Backplane Connectors

High-speed networking blade servers, router modules, and enterprise storage racks requiring 30–50 μin hard gold on edge fingers to sustain continuous hot-swap insertions without copper flaking or channel attenuation.

Automotive BMS & ECU Subsystems

Battery management interconnections and vehicle power distribution controllers exposed to continuous mechanical vibration, engine bay thermal shock, and aggressive saline humidity.

Medical Diagnostics & IVD Cartridges

In-vitro diagnostic modules, clinical blood gas monitors, and portable imaging equipment requiring zero biocompatible leaching, zero oxidation, and stable microvolt contact integrity.

Robotics & Factory Automation PLCs

Rotary encoders, slip rings, and tactile membrane switch contacts subject to hundreds of thousands of actuation cycles in harsh chemical and industrial manufacturing environments.

Emerging Trends & Global Sourcing Requirements

Strategic insights for hardware procurement executives adapting to rapid industry shifts and technological evolution.

Selective Dual-Finish Architectures

Leading hardware designers increasingly demand Selective Hard Gold + ENIG/OSP on the same circuit board. Plating hard gold strictly on edge connectors while applying ENIG or OSP on SMT pads avoids solder embrittlement (gold embrittlement occurring above 3% Au concentration in solder joints).

Strict IPC-4552B Compliance Audits

Western aerospace, defense, and telecom OEMs have moved beyond visual checks to mandate complete metallurgical cross-section reports, XRF thickness distribution charts, and X-ray porosity scans to qualify Chinese contract manufacturing partners.

Cobalt-Free Ecological Electrolytes

Driven by EU RoHS, REACH, and ESG supply chain governance, modern electroplating chemistry is advancing toward next-generation ecological cobalt-free and low-cyanide Au-Ni plating formulations without sacrificing Knoop hardness or surface finish integrity.

Frequently Asked Questions (FAQ)

Addressing engineering specifications, selective plating, DFM rules, and international procurement processes.

What is the critical difference between electrolytic hard gold and immersion gold (ENIG)?

Electrolytic hard gold is an electrodeposited alloy containing trace cobalt or nickel (0.1–0.3%), achieving a Knoop hardness of 130–200 HK and thicknesses from 15 to 50 microinches. It is designed specifically for frictional wear resistance (e.g., PCIe gold fingers). In contrast, ENIG is a chemical displacement process yielding 99.9% soft pure gold at only 1–3 microinches (60–90 HK), designed exclusively for flat surface-mount component soldering and non-sliding contact pads.

Why is electrolytic hard gold unsuitable for standard SMT solder joints?

When molten solder contacts a thick gold deposit (>10 microinches), the gold dissolves rapidly into the tin matrix, forming brittle AuSn4 intermetallic compounds. If the weight percentage of gold in the resulting solder fillet exceeds 3%, it causes severe "gold embrittlement," drastically reducing solder joint shear strength and resulting in catastrophic joint fracture under thermal or mechanical stress. Hence, selective hard gold is isolated to connector tabs, while SMT pads receive ENIG, OSP, or Immersion Tin.

What Gerber files and DFM rules are required for selective hard gold edge fingers?

You must provide dedicated plating busbar layers or specify the connector fingers requiring galvanic connection during board panelization. Include an edge beveling mechanical drawing specifying the chamfer angle (standard 20°, 30°, or 45°) and residual depth (usually 0.5mm minimum). Solder mask clearances around fingers must be maintained at a minimum of 3 to 5 mils to avoid mask bleed onto frictional contact areas.

How does Aozite verify plating thickness and eliminate porosity defects?

We utilize calibrated X-ray Fluorescence (XRF) spectrometry measuring both nickel barrier thickness (100–200 μin) and hard gold thickness across multiple panel zones to guarantee uniform current distribution. Porosity testing is conducted according to ASTM B735 (nitric acid vapor exposure) or ASTM B799 (gel-bulk electrographic method) to verify zero exposed nickel or micro-void pinholes before line assembly.

Can overseas clients conduct remote live video audits or factory tours before signing volume purchase orders?

Yes. Enterprise procurement teams can schedule an on-site visit to our Shenzhen facility or request an interactive HD video audit led by our chief quality engineers. Our walkthroughs cover our ESD-controlled chemical plating baths, automated 8-line SMT workshops, 3D SPI and inline AOI/AXI inspection stations, incoming MSD dry chambers, and complete lot traceability systems.

High-Mix OEM / ODM Electronic PCBA Capabilities

Explore additional high-density assembled circuit boards engineered with turnkey quality control and rapid prototyping capabilities.