Can Neway customize DMLS parameters for specific Inconel alloys per customer needs?
From a manufacturing engineering and quality assurance perspective, the ability to customize DMLS parameters for specific Inconel alloys is not just an option but a fundamental requirement for producing flight-critical, high-integrity components. At Neway, this capability is a core competency, grounded in a rigorous, data-driven methodology that ensures each customer's specific mechanical, microstructural, and performance requirements are met.
The Capability for Parameter Customization
Yes, Neway possesses the engineering expertise and technological infrastructure to fully customize DMLS process parameters for specific Inconel grades. This is not a simple adjustment of a few settings; it is a comprehensive development process tailored to the unique chemical composition and performance needs of alloys such as Inconel 718, Inconel 625, and others. This customization is essential because "Inconel" represents a family of alloys, each with different strengthening mechanisms and phase stability windows that demand precise thermal management during printing.
The Parameter Development Process
The customization follows a structured, iterative engineering approach:
Requirement Analysis: The process begins by defining the critical-to-quality (CTQ) attributes for the part. This includes ultimate tensile strength, yield strength, elongation, fatigue life, creep resistance, and specific microstructural requirements (e.g., grain size, absence of deleterious phases).
Design of Experiments (DOE): Our engineering team designs a DOE that systematically varies key parameters:
Laser Power, Scan Speed, and Hatch Spacing: The core "energy density" parameters that control melting and solidification.
Layer Thickness: Affects resolution, surface finish, and build rate.
Scan Strategy: The laser path pattern (e.g., stripe, chessboard) which is critical for managing residual stress and minimizing anisotropy.
Pre-heat Temperature: Especially important for crack-prone alloys to reduce thermal gradients.
Test Coupon Fabrication and Analysis: Test coupons are printed using the parameter sets from the DOE. These coupons undergo a battery of tests:
Mechanical Testing: Tensile, fatigue, and hardness tests to validate performance against CTQs.
Metallurgical Analysis: Microscopy (SEM/OM) to examine grain structure, identify any porosity, and ensure the absence of cracks or unwanted precipitates.
Density Measurement: To achieve >99.9% density, verifying that the parameters eliminate internal defects.
Parameter Lockdown and Qualification: The optimal parameter set is selected, documented, and locked down for production. This parameter set becomes part of the qualified manufacturing process for that specific alloy and application.
Integration with Post-Processing
Parameter customization is intrinsically linked to the post-processing workflow. The developed DMLS parameters are designed to produce an "as-built" microstructure that responds predictably to essential post-processes, ensuring final performance:
Hot Isostatic Pressing (HIP): Custom parameters ensure the part has a sound initial structure so that HIP can effectively close any residual microscopic pores without causing grain coarsening.
Heat Treatment: The parameters are co-developed with the heat treatment cycle. For instance, for Inconel 718, the build parameters are optimized to minimize the formation of Laves phase, ensuring the subsequent solution and aging treatment can optimally precipitate the strengthening gamma double prime (γ") phase.
Support Structure Strategy: Parameter customization also extends to support structures, optimizing their design and laser parameters to ensure successful build completion and easy removal without damaging the part.
Engineering Assurance and Quality Control
This entire process is underpinned by a robust quality management system, often including NADCAP accreditation for additive manufacturing. We provide full traceability and documentation, including:
Certification of the metal powder lot.
Records of the machine calibration and environmental conditions during the build.
Mechanical test reports from witness coupons built alongside production parts.
Non-destructive testing (NDT) reports, such as CT scanning, to verify internal integrity.
In conclusion, Neway does not simply run off-the-shelf parameters. We employ a sophisticated, collaborative engineering process to develop and qualify custom DMLS parameters that are integral to delivering Inconel components that meet the precise performance, life cycle, and reliability demands of our customers in the aerospace, power generation, and oil & gas sectors.
