Statement of Requirements.pdf

STATEMENT OF REQUIREMENTS

Dynamic Directed Energy Deposition System

I. BACKGROUND INFORMATION

The Materials Measurement Science Division (MMSD) in the Material Measurement Laboratory (MML) at the National Institute of Standards and Technology (NIST) advances measurement science, standards, and technology to support the industrialization of advanced manufacturing. A critical national need is the development of metrology tools that reliably link materials composition, processing conditions, structure, and performance - particularly in metal-based additive manufacturing (AM), where rapid solidification under extreme conditions presents major challenges to microstructure control.

To address these challenges, MMSD is developing a high-speed X-ray metrology platform capable of probing materials’ structural evolution in real time during AM processes. Current high-speed X-ray diffraction (XRD) measurements are limited by slow sample preparation and fixed compositions, restricting systematic exploration of the vast composition–processing space critical to understanding AM. The inability to measure dynamic phase transformation behavior at relevant time and length scales remains a significant barrier to AM’s broader industrial adoption.

The Contractor shall provide a dynamic powder-based directed energy deposition system specifically designed to enable real-time structural characterization of materials during additive manufacturing processes. The system shall meet the minimum technical specifications detailed in the Specifications section of this Statement of Requirements.

The Contractor shall deliver a complete, fully functional system including hardware, software, and associated components necessary for dynamic multi-powder deposition and integration with high-speed X-ray scattering measurements.

The Contractor shall also perform system installation and provide training and documentation to support NIST’s safe and effective operation of the system, as detailed in the Specifications section.

II. SPECIFICATIONS

1. System Overview The Contractor shall provide a floor-standing, powder-based, laser-driven directed energy deposition system designed for high-throughput, dynamic composition control during deposition. The system shall be suitable for in situ integration with high-energy X-ray scattering beamlines and capable of fabricating thin-walled metallic structures under controlled atmospheric or vacuum conditions.

Figure 1: Schematic of the coordinate system used for the build volume and beamline alignment.

The X-ray beam propagates horizontally from upstream to downstream along the Y-axis, while the laser beam is incident vertically along the negative Z-axis. The X-axis is orthogonal to both the X-ray and laser beam directions, completing the right-handed coordinate system.

2. Build Volume and Motion

• Build Volume, which is defined by linear sample motion:

o Minimum X-axis travel (horizontal, perpendicular to X-ray beam): 100 mm o Minimum Y-axis travel (horizontal, along X-ray beam direction): 10 mm o Minimum Z-axis travel (vertical): 25 mm o Build volume shall be translatable within the center of the x-ray beampath (defined by centerline of x-ray windows below, see Figure 2) o An additional 50 mm of clearance between the bottom build volume and the top of the motion system is necessary to allow for tooling and other sample stage equipment. This can be achieved, for instance, through additional motorized Z travel, a moveable stage stack, or a spacer.

o The Y axis shall not be the top axis in the motion stack.

• Print Head and Laser Motion:

o The print head, including the laser and powder nozzle, shall have independent motion along three axes:

Horizontal (parallel to build plate X-axis) with a minimum travel distance of 100 mm.

Perpendicular (parallel to the X-ray beam direction) with a minimum travel distance of 10 mm.

Vertical (parallel to build plate Z-axis) with a minimum travel distance of 50 mm.

• Motion Control:

o All motion axes (build plate and print head) shall be motor-driven by stepper or servo motors.

o Positioning repeatability across all axes shall be within ±1 µm.

o Minimum traverse speed across all axes shall be at least 100 mm/min.

• Print Head Distance Monitoring o The print head shall include a non-contact distance measurement mechanism (e.g., laser triangulation sensor or equivalent) capable of measuring the distance between the print head and the top surface of the deposited material during the build process.

o The distance measurement system shall maintain a consistent stand-off distance during dynamic layer deposition.

o The distance measurement mechanism shall have a measurement accuracy of ±20 µm or better and a response time compatible with continuous deposition operations.

3. Powder Delivery System

• Powder Feeders:

o Minimum of four (4) independently controllable powder hoppers.

o Powders shall be mixed prior to being dispensed out of the nozzle o Real-time dynamic powder mixing capability during deposition.

o Powder shall reach new composition 30 s following change composition command.

• Composition Control:

o Composition accuracy within ±10% of the target value (e.g., a target composition 5% for a weight fraction must be within 4.5% to 5.5%), across a 1%–100% weight fraction range.

• Powder Specifications:

o Hoppers shall handle spherical powders with particle size diameter range of at least

45 µm and 150 µm.

• Expandability:

o System shall be expandable to allow addition of 2 more powder hoppers if needed.

• Powder nozzle:

o Powder shall be delivered coaxially with the laser beam.

4. Laser System

• Type:

o Fiber laser (e.g., Ytterbium or equivalent).

• Power:

o The system shall be equipped with an industrial-grade continuous wave (CW) fiber laser from a reputable manufacturer such as IPG Photonics, nLight, or an equivalent vendor approved by NIST.

o The laser shall have a minimum rated output of 500 W, with a power stability of ±2% or better over the full operating range.

• Wavelength:

o Operating wavelength range between 900 nm and 1080 nm.

• Spot Size:

o Adjustable (preferred) or fixed spot size between 400 µm and 1 mm.

• Laser Safety:

o The laser source shall be certified to applicable industrial safety standards and compatible with Class 4 laser safety protocols.

o The laser system shall incorporate a fully integrated interlock system to prevent inadvertent laser exposure to personnel.

o All access doors and windows (covers) of DED build chamber shall be interlocked to the laser operation control system.

• Interlock and Laser Safety System Requirements

The system shall support two distinct interlock modes of operation to ensure compliance with both internal and external laser safety protocols:

o In-House Operation Mode (Chamber-Controlled):

Laser emission shall be permitted only when the chamber door is securely closed and the X-ray-transparent window covers are in place.

In this configuration, the chamber itself defines the controlled laser area.

o Synchrotron Hutch Operation Mode (Room-Controlled):

Laser emission shall be permitted when the chamber door is closed and an external interlock mechanism (provided by the synchrotron facility) is activated.

Window covers for the X-ray entry and exit ports shall not be required in this mode to allow uninterrupted high-energy X-ray beam access.

In this configuration, the entire hutch becomes the designated interlocked laser control area.

Figure 2: Schematic (side view) illustrating the required X-ray beam alignment through the build volume. The X-ray beam enters from the right through the beam entry port and exits to the left through the beam exit port. After interacting with the build volume, the system must accommodate a minimum scattering angle of ±20° relative to the beam axis through the exit port. A minimum unobstructed clearance of 300 mm between the entry and exit chamber walls is required. The centers of the entry and exit ports must be aligned along the X-ray beam propagation direction.

5. Chamber and Atmosphere Control

• Chamber Design:

o Enclosed, sealed environment suitable for controlled atmosphere processing.

o Minimum internal clearance of 300 mm along the beam direction.

o The chamber shall include modular mounting surfaces (e.g., breadboard-style plates or equivalent) on at least the upstream wall to enable flexible installation of internal components. The design and choice of mounting surfaces shall consider purge compatibility to minimize trapped volumes and facilitate efficient chamber purging.

Chamber door shall be on the downstream (of the X-ray beam traveling direction) end of the chamber. Door shall be openable/closeable by one person.

o A laser-opaque optical viewport shall be installed on the chamber door.

• X-ray Beam Access o The chamber shall include an upstream incident beam entry port and a downstream scattered beam exit port to accommodate high-energy X-ray scattering measurements.

o The centers of the entry port and exit port for X-rays shall be aligned colinearly along the intended X-ray beam path to ensure unobstructed transmission.

o The X-ray beam path must remain unobstructed, except for the deposited material being monitored during the process.

o The Beam Entry Port shall use an ISO-K style flange (or equivalent) and be bulkhead mounted to maintain atmospheric integrity. The port dimension must be no less than 100 mm in diameter.

o The Beam Exit Port shall use an ISO-K style flange (or equivalent) and be bulkhead mounted to maintain atmospheric integrity. The port shall have an inner diameter sufficient to accommodate a vector with a takeoff angle of at least 20 degrees from the build volume (typically thin-wall structures). The inner diameter must be no less than 150 mm in diameter.

o The ports shall be supplied with a blank flange and all necessary sealing hardware (e.g., centering rings, O-rings, and clamping hardware) for each window port.

o The X-ray ports shall include removable laser-tight window covers to be placed over the blank flanges that are interlocked with the laser safety system, preventing laser operation when covers are removed or improperly installed.

o A KF-50 port shall be installed on the side wall of the chamber, aimed at the center of the x-ray beam path, coming in at an angle between 30° and 45° to the horizontal.

• Oxygen Purging Mechanism:

o System shall include capability to rapidly and reliably reduce oxygen levels to ≤50 ppm prior to deposition within 30 min.

o An integrated oxygen sensor capable of real-time monitoring down to at least 50 ppm shall be installed, with accessible readout.

• Gas Handling:

o Inlet and outlet ports for argon flow management.

o Integrated overpressure relief valve for chamber safety.

6. Software and Controls

• Control System:

o PC-based control compatible with Windows 10/11 or Linux operating systems.

• Hardware Control and Operation Requirements:

o The system shall include an API or programmatic control library that enables external control and monitoring of:

Deposition parameters (e.g., powder composition, laser power, motion control).

Process synchronization.

Real-time telemetry access (e.g., build coordinates, scan settings, chamber conditions, laser parameters).

o Comprehensive documentation for the interface shall be provided, including user guides, reference manuals, and example code snippets

• Synchronization and Data Acquisition:

o System shall have the option to accept TTL input signals to trigger process start/stop.

o System shall generate TTL output signals indicating process events (e.g., laser on, layer start).

• Metadata Logging:

o System shall automatically log laser parameters, powder composition settings, build coordinates, chamber conditions, and scan settings.

7. Mechanical Integration Requirements

• System Weight:

o Chamber weight shall not exceed 800 lbs (excluding ancillary equipment).

• Mounting and Alignment:

o Adjustable leveling feet allowing precise leveling.

o Lifting points for forklift or eye bolt-based movement.

• Footprint:

o System footprint shall not exceed approximately 1000 mm × 1000 mm (excluding ancillary equipment).

8. Powder Collection and Management

• Powder Collection:

o The system shall include a powder collection method to safely and efficiently recover unused and oversprayed powder after the build is completed. The collection method may involve post-build manual vacuuming, provided it supports safe operator access, powder containment, and compliance with metallic powder handling best practices.

• Powder Handling Safety:

o Chamber systems must be designed to minimize airborne powder release and support safe operator handling.

9. Installation

• Contractor shall install the system at NIST Gaithersburg, MD in 223/A242 .

• Installation shall include complete setup, calibration, demonstration of all functions, including a complete and functional build using the integrated deposition system (laser, motion, powder delivery, and control software), and removal of packing materials.

• The system shall demonstrate compliance with all specifications upon installation.

10. Training

• Contractor shall provide onsite training for up to two (2) NIST personnel.

• Training shall include system operation, safety procedures, maintenance, and troubleshooting.

• Training will be provided during normal business hours, between 8:30am and 5:00pm

Eastern Time, Monday through Friday, except Federal Holidays, and will be coordinated with the Contracting Officers Representative (COR) to ensure maximum availability of NIST personnel. Training may be completed on-site NIST immediately after installation and demonstration of specifications.

11. Warranty

• Contractor shall provide a minimum one-year comprehensive warranty covering all parts, labor, and travel.

• Warranty shall commence upon acceptance by the COR.

Documentation

• The Contractor shall provide an operations and maintenance manual in electronic (PDF) format, and if available, hard copy.

III. DELIVERY

Delivery shall be within 240 days from award to 223/A150 between the hours of 8:30am to 5:00pm Eastern, Monday through Fridays, except Federal Holidays.

IV. PLACE OF PERFORMANCE

All work shall be completed at the Contractor’s facility. Installation of the instrument and training shall be accomplished at NIST, Gaithersburg, Maryland. Normal duty hours are Monday through Friday, 8:30 a.m. to 5:00 p.m. with the exception of Federal holidays.

V. DELIVERABLES

Description Quantity Due Date A dynamic powder DED system One (1) 240 days after award of this requirement.

Installation of the equipment Once 240 days after award of this requirement.

Operations and maintenance manual for the DED equipment

One (1) 240 days after award of this requirement via electronic format (PDF) and hard copy upon request.

Training of NIST personnel at NIST, Gaithersburg, MD

Once 10 days after installation.

VI. ACCEPTANCE CRITERIA

The Contractor shall demonstrate that all performance specifications are met including demonstrating a complete build using the integrated deposition system (laser, motion, powder delivery, and control software).

A preliminary design review shall be completed and approved by the COR prior to the start of fabrication. The vendor shall submit detailed design documentation (including chamber configuration, motion architecture, laser integration, and planned control interfaces) within 60 calendar days of award. NIST will provide feedback within 10 business days of submission.

VII. GENERAL INFORMATION

Safety: The Contractor employee shall be responsible for knowing and complying with commercial installation safety prevention regulations. Such regulations include, but are not limited to, general safety, fire prevention, and waste disposal.

Security: NIST is a restricted campus. An identification badge is required for access for entry into buildings and also is shown to the armed Security Police when entering the campus.

Vehicle Registration: All Contractor employees must register their vehicles with the NIST Security Office to gain access to the campus. A valid driver’s license, Government-furnished civilian ID (which in most cases can be a valid driver's license), proof of insurance and current registration must be presented to the NIST Security Office.