Neway's Quality Assurance for Welded High-Temperature Alloys: HIP, PWHT & NDT

How Neway Ensures Quality in Welded High-Temperature Alloy Components

Neway Aerotech ensures the quality of welded high-temperature alloy components through a rigorous, multi-stage quality management system that integrates advanced technology, specialized post-process treatments, and stringent validation protocols. This holistic approach guarantees that every welded component meets the extreme demands of aerospace and aviation and power generation applications.

1. Pre-Weld Qualification and Process Control

Quality begins long before the welding arc is struck. Neway's process is founded on meticulous preparation:

• Procedure Qualification: Every welding procedure is rigorously developed and qualified according to international standards (e.g., AWS, NADCAP). This defines and validates all critical parameters, including heat input, filler metal, and shielding gas.

• Material Verification: The base and filler materials are certified to ensure correct chemistry and properties, preventing incompatibility issues that could lead to cracking or failure.

2. Precision Welding with Advanced Technology

We employ high-precision, low-heat-input processes like Electron Beam (EB) and Laser Welding to minimize thermal distortion and the size of the Heat-Affected Zone (HAZ). These automated and semi-automated processes ensure exceptional consistency and repeatability, eliminating human error from critical weld parameters.

3. Mandatory Post-Weld Treatments for Property Restoration

This is the cornerstone of Neway's quality assurance for welds. We systematically reverse the detrimental effects of welding through:

• Hot Isostatic Pressing (HIP): Applied to critical welds, HIP uses high temperature and isostatic gas pressure to heal internal defects like porosity and micro-cracks within the weld metal. This is vital for achieving maximum fatigue strength and fracture toughness.

• Post-Weld Heat Treatment (PWHT): A carefully engineered heat treatment cycle is mandatory. It serves to:

  1. Relieve Residual Stresses: Significantly reduces the tensile stresses locked in from welding.

  2. Re-homogenize Microstructure: Dissolves deleterious phases and promotes a uniform structure in the HAZ and fusion zone.

  3. Restore Mechanical Properties: Re-precipitates the strengthening gamma prime (γ') phase to recover creep and tensile strength.

4. Comprehensive Inspection and Validation

Every welded component undergoes a battery of non-destructive and destructive tests to verify its integrity:

• Non-Destructive Testing (NDT): We utilize Fluorescent Penetrant Inspection (FPI) for surface defects and Radiographic Testing (RT) for internal defects to ensure the weld is free of discontinuities.

• Dimensional Verification: Precision superalloy CNC machining is often used after PWHT to restore final dimensions, which are then verified using Coordinate Measuring Machines (CMMs).

• Material Testing and Analysis: This is our final validation. We perform metallographic cross-sectioning to examine the weld's macrostructure and microstructure, ensuring proper fusion, absence of cracks, and a sound HAZ. This may be complemented by mechanical testing to validate properties.

5. Systemic Quality Culture and Certifications

Underpinning all technical processes is a culture of quality, often audited and certified under stringent aerospace accreditation programs like Nadcap (National Aerospace and Defense Contractors Accreditation Program) for both heat treatment and welding. This ensures that our entire quality management system—from material procurement to final shipment—is robust, documented, and continuously improved.

In summary, Neway ensures quality not by relying on a single inspection step, but by building it into every phase of the superalloy welding value chain. From qualified procedures and precision welding to defect-healing HIP, microstructure-restoring PWHT, and final validation, we deliver welded components with guaranteed performance and reliability.