Facilities – Materials for Extreme Environments

Overview

The Texas A&M University (TAMU) Hypervelocity Impact Laboratory (HVIL) is located at the Center for Infrastructure Renewal (CIR) at RELLIS campus of The Texas A&M University. The laboratory research is aimed at enabling unique high-rate materials characterization and multiscale numerical model development and implementation. The TAMU HVIL, operated by a team of distinguished researchers, provides a testbed for the development and tailoring of novel monolithic, layered, and architected structures comprised of polymers, composites, metals, ceramics, soft materials, gels, and geomaterials to mitigate HVI threats (e.g., hypersonic weapons, micrometeoroid/orbital debris, atmospheric reentry conditions). The laboratory currently houses a state-of-the-art two-stage light gas gun (2SLGG) capable of launching 0.8-12.7 mm diameter projectiles at velocities in the range of 1.5-8.0 km/s (3,355-18,000 miles/hr). Projectile materials currently include steel, aluminum, nylon, glass, polycarbonate, tungsten, and titanium. The modern and advanced facility at HVIL allows for targets of many sizes, shapes, and weights to be impacted efficiently and reliably at normal and oblique orientations. A brief description of the 2SLGG can be found here. The 2SLGG is currently equipped with a pair of laser intervalometers, an ultra-high-speed camera, a dual-head 450 kV flash X-ray system, high-speed Schlieren imaging, and novel particle tracking technology. Ongoing developments include advanced digital in-line holography diagnostics and modern target heating/cooling techniques. Future diagnostic equipment will include an additional high-speed camera(s), high-speed thermal camera(s), and a photon doppler velocimetry (PDV) system.

Quick Facts

2SLGG Specifications

Testing Specifications

Diagnostics and Testing Features

Ultra-high Speed Camera (up to 10 million fps)

Frame rates up to 10 million fps
128 or 256 frames
Down to 50 ns of exposure
Accompanying high-power LED lights

Laser Intervalometer & Dynamic Delay Generator

Main instrument for determining projectile velocity
Velocity errors below 2 m/s at a projectile velocity of 8,000 m/s
Highly reliable and repeatable measurements
Rapidly adjustable and robust dynamic delay generator

Flash X-ray System (450 kV)

Pulsing voltages ranging from 150 kV to 450 kV
Dual head setup allows for two spatially and/or temporally varied radiographs
Pulse duration of 20 ns

Ultra-high Speed Schlieren Imaging

Robust setup that uses high-speed camera (up to 10 million fps)
Enables high-speed images of relative density gradients
Allows for the in-situ characterization of shock-projectile, shock-particle/fragment, and shock-shock interactions

Particle Tracking

Novel computational techniques enable the extraction of particle and flow field data
Applicable to high rate, high temperature environments
Provides size, position, velocity, temperature, and elemental composition of fragments produced during hypervelocity impacts

Single-Stage Launcher Modifications

Impact research problems at lower velocities can be addressed
Utilizes existing 12.7 mm bore
Faster experimental throughput

See us in action

See a brief overview of our capabilities and how we perform hypervelocity impact experiments at the Texas A&M University (TAMU) Hypervelocity Impact Laboratory (HVIL).

Interested in HVI testing?

If you are interested in hypervelocity impact testing at the Texas A&M Hypervelocity Impact Laboratory, please complete the form here. A researcher will contact you within one week.

Lab Founder & Director

Dr. Thomas E. Lacy Jr.

Professor, Mechanical Engineering
telacyjr@tamu.edu
662-648-9213

Affiliated Researchers

Kalyan Raj Kota
Waruna Kulatilaka
Justin Wilkerson
Brian Schuster
Jacob Rogers
Aniket Mote
Paul Mead
Khari Harrison
Dean Biava
Michael Rakoski

Gavin Lukasik
Max Murtaugh
Cullen Miller
Nathaniel Bass
Matthew Intardonato
Sidney Davis
Mikayla Wiest
Brynn Martin
Sarah Beth Ragan

Laboratory Render

2SLGG Experience

The Materials for Extreme Environments (MEE) team has over a decade of experience developing, enhancing, and employing two-stage light gas guns (2SLGGs). In addition to the 12.7-bore 2SLGG located at the Texas A&M University Hypervelocity Impact Laboratory (HVIL), the Materials for Extreme Environments team, under the direction of Prof. Thomas Lacy, established two 2SLGGs at Mississippi State University (MSU). The countless lessons learned in creating these previous laboratories informed and motivated design and procedural enhancements over the years that led to an overall increase in testing reliability, efficiency, and safety. Our team prides ourselves in our ability to not only institute cutting-edge facilities but also create a culture of innovation that leads to perpetual novel improvements in testing and diagnostic capabilities.

First 2SLGG

The first 2SLGG, small scale (up to 1 mm diameter projectiles) compared to the HVIL 2SLGG, enabled a variety of research, including studying the effects of shear-thickening-fluid-filled honeycomb composites on hypervelocity impact (HVI) performance. The gun was capable of launching smaller projectiles to velocities ranging from 2-8 km/s. The lessons learned from this 2SLGG in part motivated the design of the second 2SLGG.

Second 2SLGG

The second 2SLGG was much larger with a maximum projectile diameter of 4 mm. This gun could launch such projectiles to velocities exceeding 7 km/s. It is evident that the design of this 2SLGG is a slightly different, smaller scale version of the HVIL 2SLGG. The target tank is quite similar, with the 45 and 90 deg windows being the main difference. Like before, the lessons learned from operating this 2SLGG led to design changes for the HVIL 2SLGG, including larger launching capabilities, more sophisticated (pneumatic) valves, more diagnostic windows and through ports, a larger blast tank, digital pressure transducers, and a comprehensive control panel. The desire for a larger launch capability (6.35 mm bore to 12.7 mm bore) led to a 30% increase in the length of the HVIL 2SLGG compared to the MSU 2SLGG.