I. Core Service Capabilities and AS9100D Compliance Analysis

　　1. Key Compliance Points of AS9100D Standard

　　Special Requirements for Quality Management System: Meets the basic framework of ISO 9001:2015, with additional enhancements to aerospace-specific clauses: including 8.1.3 "Product Safety" (requires identification of safety-critical PCBA components in avionics systems, such as the power supply circuit of the engine control unit PCB), 8.3.6 "Design and Development Change Control" (any process/component changes must be approved by the aerospace customer's PRR (Engineering Change Request), and 9.1.3.1 "Product Conformity Monitoring" (full-process data record retention period ≥ 15 years, covering the entire lifecycle of aerospace products).

　　Risk Management: Performs FMEA (Failure Mode and Effects Analysis) as required by AS9100D, identifies potential failure modes (such as solder joint voids leading to avionics signal interruption) for key PCBA processes (such as BGA soldering and conformal coating), and develops preventative measures (such as optimizing reflow soldering profiles and increasing X-ray full inspection).

　　Configuration Management: Establish a strict product configuration control process. Each batch of PCBA corresponds to a unique configuration number, linked to design documents (Gerber, BOM), process parameters, and test reports to ensure consistency and traceability across different batches.

　　2. Core Process Technology for Aerospace-Grade PCBA

　　Substrate and Component Selection (Aerospace-Grade Standards):

　　PCB Substrate: Select aerospace-certified substrates, such as polyimide (PI) substrate (temperature resistance -65℃~260℃, suitable for the high-temperature environment of engine compartments) and PTFE (polytetrafluoroethylene) substrate (low dielectric loss, suitable for high-frequency avionics systems such as radar and communication). The substrate must meet the UL 94 V-0 flame retardant standard and AS9100D's requirements for "material traceability" (provide the original manufacturer's COA (analysis report)).

　　Component Selection: Only aerospace-grade components are used, conforming to MIL-PRF (Military Performance Specification), EN 9100 (European Aeronautical Standard), or SAE AS5953 (Component Qualification). Industrial/commercial-grade components are prohibited. Key components (such as MCUs and power chips) must possess "radiation hardness" characteristics to withstand total radiation dose in aerospace scenarios (≥100 krad (Si)).

　　Soldering Process: Aerospace-grade lead-free solder (such as SAC305, conforming to MIL-SPEC 3288) is used. Reflow soldering temperature profiles are customized according to the original component manufacturer's aerospace-grade specifications (e.g., peak soldering temperature of 245℃±3℃ for high-temperature components, holding time ≤60 seconds). BGA/QFP devices are required to use an "underfill" process (epoxy adhesive must conform to NASA SP-R-0022 standard) to improve vibration and thermal cycling resistance. Special Processes and Protective Design:

　　* **Conformal Coating:** Aerospace-certified coating materials are used, such as polyimide coating (temperature resistance -65℃ to 200℃, resistant to aviation fuel/hydraulic oil corrosion) and silicone coating (suitable for low-temperature aerospace applications). Coating thickness is controlled between 75μm and 150μm, with 100% coverage (including component pin gaps), conforming to IPC-CC-830B standards.

　　* **Electromagnetic Compatibility (EMC) Design:** Following the requirements of Chapter 20, "Electromagnetic Compatibility," of RTCA DO-160 (Environmental Conditions and Test Procedures for Avionics Equipment), the PCB employs a "separate analog/digital ground" and "high-frequency signal shielding layer" design. Key interfaces (such as ARINC 429 and CANaerospace) are equipped with EMI filters to ensure signal distortion-free operation in strong electromagnetic environments (such as radar emissions and engine interference) on aircraft.

　　Mechanical Hardening: For aviation vibration scenarios (such as aircraft takeoff/landing impact), aerospace-grade aluminum alloy reinforcement frames (material 6061-T6, conforming to AMS-QQ-A-250/11 standard) are added to the edges of the PCBA. Connectors use locking type (such as Micro-D, D38999 aviation connectors) to prevent pin detachment due to vibration.

　　3. Full Lifecycle Traceability System

　　Component Traceability: A four-level correlation system is established: "Component Batch Number - COC/COA Document - Production Work Order - Test Report". Each component can be traced back to the original manufacturer's production batch and quality inspection data; aerospace-grade components require additional records of specialized certification documents such as "Radiation Test Report" and "Temperature Cycling Test Data".

　　Mixed batches of components are prohibited. Key components in the same batch of PCBA (such as the same model MCU) must come from the same original manufacturer's batch to ensure performance consistency.

　　Production Process Traceability: Each process (particle placement, soldering, coating, testing) records the operator, equipment number, process parameters (such as reflow soldering temperature profile, coating thickness measurement values), and timestamp. Data is uploaded in real-time to the QMS (Quality Management System) required by AS9100D, supporting remote access by the customer.

　　First Article Inspection (FAI): First article approval is performed according to AS9102 standards. The first PCBA of each batch must pass all tests (electrical performance, environmental adaptability, EMC), and an FAI report (including 3.1 "Design Data" and 3.4 "Characteristic Test Results") must be submitted. Mass production can only commence after customer approval.

　　II. Environmental and Reliability Testing (Aerospace-Specific Standards)

　　1. Aerospace Scenario Testing Items (Compliant with RTCA DO-160)

　　Temperature and Thermal Cycling Testing:

　　High-Temperature Operation: 125℃ for 1000 hours (simulating engine compartment environment), with PCBA electrical performance parameters (such as impedance, signal transmission rate) deviating by ≤5% after testing;

　　Low-Temperature Operation: -65℃ for 1000 hours (simulating high-altitude low-temperature environment), with no component failure or solder joint cracking;

　　Temperature Cycling: -55℃ to 125℃ for 2000 cycles (transition time ≤5 minutes), each cycle consisting of 1 hour of high temperature and 1 hour of low temperature, with no coating peeling and connector contact resistance ≤10mΩ after testing.

　　Mechanical Environment Testing:

　　Vibration Testing: According to RTCA DO-160 Chapter 8, frequency 5Hz~2000Hz, acceleration 20g (sine vibration), 10g (random vibration), 2 hours of testing in each axis. After testing, the PCB showed no deformation and solder joints showed no voids.

　　Impact Testing: According to RTCA DO-160 Chapter 9, half-sine impact (peak acceleration 50g, duration 11ms) and sawtooth wave impact (peak acceleration 30g, duration 100ms), 3 times in each axis. No structural damage or functional failure was observed.

　　Constant Acceleration: According to RTCA DO-160 Chapter 10, 100g acceleration (lasting 60 seconds), simulating an aircraft crash protection scenario. Key PCBA components (such as power modules) showed no displacement.

　　Fluid and Chemical Environment Testing:

　　* Aviation Fuel/Hydraulic Oil Tolerance: Immersed in Jet A-1 aviation kerosene and Skydrol LD-4 hydraulic oil for 48 hours, no coating dissolution and no corrosion of component leads;

　　* Humidity Testing: 95% RH (40℃, no condensation) for 500 hours, insulation resistance ≥100MΩ, no leakage.

　　2. Aerospace Scenario-Specific Testing (Compliant with NASA/ESA Standards)

　　* Radiation Environment Testing:

　　* Total Dose Radiation: According to NASA SP-8330 standard, the radiation dose is 100 krad (Si) ~ 1 Mrad (Si) (customized according to orbital altitude). After testing, the NPU/MCU logic functions normally, and no memory data is lost;

　　* Single Event Effect (SEE): According to ASTM E544 standard, simulating high-energy particle impacts in space, the PCBA test showed no single event upset (SEU) or single event lock-in (SEL) phenomena.

　　Vacuum and Thermal Vacuum Testing:

　　Vacuum Testing: 1000 hours of continuous operation under a 1×10⁻⁶ Pa vacuum environment, with no component outgassing (total outgassing ≤1%, condensable volatiles ≤0.1%);

　　Thermal Vacuum Cycling: 100 cycles under a vacuum environment of -65℃ to 150℃, with no cracking of the PCB substrate and no oxidation of solder joints after the test.

　　Test Report Requirements: All tests must be performed by an AS9100D certified laboratory. Reports must include "test standard number, equipment parameters, raw data curves, and pass/fail criteria," and can be submitted to aerospace regulatory agencies (such as FAA, EASA, NASA) for review.

　　III. Applicable Scenarios and Industry Adaptation Solutions

　　1. Aviation Scenarios

　　Aircraft Avionics Systems (e.g., flight control units, navigation modules, communication terminals):

　　Core Requirements: High reliability (MTBF ≥ 100,000 hours), vibration/high temperature resistance, EMC compatibility (RTCA DO-160);

　　Adaptation Solution: Uses polyimide PCB substrate (Tg ≥ 280℃), aerospace-grade MCU (compliant with MIL-PRF-55342), BGA device bottom filler + aluminum alloy reinforcement frame, 100% X-ray inspection after soldering (solder joint void rate ≤ 3%), and the entire process complies with AS9100D design change control.

　　Engine Control Unit (ECU): Core Requirements: Resistance to extreme high temperatures (continuous operation at 150℃), resistance to fuel corrosion, and rapid response (signal delay ≤1ms); Compatibility: PTFE high-frequency substrate (temperature resistance 260℃), high-temperature ceramic capacitors (compliant with MIL-PRF-123), polyimide conformal coating (resistance to fuel corrosion), PCB with thick copper design (70μm copper foil) to improve heat dissipation, and testing covering all aspects of RTCA DO-160 high temperature and fluid resistance.

　　2. Aerospace Applications

　　Satellite Payload Modules (e.g., remote sensing imaging processing units, onboard computers):

　　Core Requirements: Radiation resistance (total dose 1 Mrad (Si)), vacuum environment adaptability, low power consumption (on-orbit endurance ≥ 5 years);

　　Adaptation Solutions: Radiation-hardened components (e.g., NASA-certified MCUs), solvent-free conformal coating (reducing vacuum outgassing), PCB design with 4 or more layers of buried and blind vias (increasing signal density), testing covering all NASA thermal vacuum and single-event effects tests, and data retention period ≥ 20 years.

　　Launch vehicle electronic equipment (e.g., onboard navigation system, attitude control module):

　　Core requirements: resistance to strong impact (200g acceleration), short-term high temperature (300℃ for 10 minutes), and rapid start-up (normal operation within 1 second after power-on);

　　Adaptation solution: ceramic PCB substrate (Al₂O₃, resistant to 300℃ high temperature), metal casing (316L stainless steel, impact resistant), components use lead-free high-temperature solder (melting point 280℃), testing focuses on verifying impact and short-term high-temperature resistance performance, conforming to ESA and ECSS standards.

　　IV. Key Aspects of Cooperation and Quality Control

　　1. AS9100D Certification Cooperation Process

　　Preliminary Access and Review:

　　Supplier Qualification Review: Provide AS9100D certification (must include "Aerospace PCBA Manufacturing" certification scope), calibration reports for key equipment (e.g., reflow ovens, X-ray inspection instruments complying with MIL-STD-45662), and customer case studies (e.g., proof of cooperation with aerospace engine manufacturers);

　　Confidentiality Agreement: Sign an aerospace-grade confidentiality agreement (complying with ITAR and EAR export control requirements), restrict personnel access to sensitive data, and encrypt server storage (AES-256). Joint Design and Development:

　　Design Review: Jointly conduct AS9100D-compliant design reviews with the client, focusing on PCB layout (e.g., isolation of safety-critical loops), component selection (aerospace-grade certification), and process feasibility (e.g., high-temperature soldering compatibility). A review report will be generated and retained.

　　Prototype Production: First-article production must be conducted in an AS9100D-certified workshop, with the entire process video recorded. Prototype testing covers electrical performance, environmental adaptability, and EMC. Mass production can only commence after obtaining first-article approval (FAI) from the client.

　　2. Supply Chain and Delivery Control

　　Aerospace-Grade Component Supply Chain:

　　Supplier Access: Only collaborate with AS9100D/EN 9100-certified component suppliers (e.g., Avnet Aerospace, Arrow Space & Defense). Supplier audits are conducted quarterly to ensure material compliance.

　　Procurement Cycle: Aerospace-grade component lead times are typically 16-20 weeks. Procurement planning must be done in advance. For scarce components, "long-lead-time stocking" (Minimum Order Quantity (MOQ) is customized according to customer requirements) will be implemented. Delivery and Acceptance:

　　Delivery Documents: An "AS9100D Compliance Package" will be provided with the PCBA, including a Certificate of Conformity (COC), FAI report, test data, component traceability list, and process parameter records. Documents must be signed and stamped and conform to the aerospace customer's document format requirements.

　　Acceptance Standards: Acceptance will be conducted according to the customer-defined "Aerospace PCBA Acceptance Specification," including appearance (IPC-A-610 Class 3), electrical performance (ICT/FCT full scope), and environmental testing (10% sampling for thermal cycling/vibration testing). Non-conforming products will be reworked/scrapped according to AS9100D 10.2 "Non-conforming Output Control," with closed-loop record keeping.

　　3. After-sales Service and Continuous Improvement

　　Warranty and Fault Handling:

　　Warranty Period: 5-10 year warranty (10 years for aerospace applications, 5 years for aviation applications). During the warranty period, for process issues (such as coating peeling, solder joint failure), free rework will be provided, and the customer's associated losses will be covered.

　　Fault Analysis: Upon receiving fault feedback, a "Root Cause Analysis" as required by AS9100D will be initiated within 48 hours, using the 8D method (including temporary measures, root cause verification, and corrective actions). A fault analysis report will be generated and submitted to the customer for review.

　　Continuous Improvement: In accordance with AS9100D 9.3 "Management Review" requirements, customer feedback, process data, and test results will be collected quarterly to identify improvement opportunities (such as optimizing welding curves to reduce void ratio). Improvement measures must be verified for effectiveness and recorded in the QMS system.

　　Regular internal audits of AS9100D will be conducted to ensure continuous compliance of the quality management system, and cooperation with third-party audits by customers (such as FAA and EASA on-site audits).