High Crush Strength Aluminum Honeycomb Impact Attenuator for Nuclear Spent Fuel Transport Cask End Impact Limiter

High Crush Strength Aluminum Honeycomb Impact Attenuator for Nuclear Spent Fuel Transport Cask End Impact Limiter​

 
The High Crush Strength Aluminum Honeycomb Impact Attenuator is a precision-engineered energy absorption core specifically designed for end impact limiters on nuclear spent fuel transport casks. Deployed at both the top and bottom of transport casks, this attenuator absorbs kinetic
energy and limits inertial loads during the hypothetical 9-meter (30-foot) drop accident required by 10 CFR Part 71.
 
Selected by leading cask designers for its lightweight construction, uniform density, well-defined crush strength, and non-combustible properties, this high-strength honeycomb provides the predictable, constant-force crushing response essential for regulatory compliance and nuclear safety.
 
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2. Operating Principle
Under impact loading, the aluminum honeycomb undergoes controlled plastic deformation through progressive cell-wall buckling and folding. This collapse propagates uniformly through the material thickness, converting kinetic energy into deformation work at a near-constant force level throughout the crush stroke.
The material is pre-crushed during fabrication to eliminate the initial peak stress spike, resulting in an immediate, uniform crush strength from the onset of loading. This ideal elastic-perfectly-plastic behavior enables accurate deceleration prediction and simplifies safety analysis.
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3. Key Features
Feature Benefit
High Crush Strength (2,000–3,850+ psi) Compatible with heavy casks; meets or exceeds 12.35 MPa minimum plateau stress requirement
Pre-Crushed Condition Eliminates initial peak stress; provides immediate constant-force response
Bi-Directional / Multi-Directional Configuration Uniform crush strength in multiple orientations; superior to conventional unidirectional honeycomb
Temperature Insensitive Crush strength varies <6% from –29°C to 93°C (–20°F to 200°F)
Lightweight Nominal density 22–27 lb/ft³ (adjustable); minimizes payload weight
Non-Combustible Does not burn when subjected to intense heat
Removable & Interchangeable Facilitates inspection, repair, and decontamination
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4. Application: Spent Fuel Transport Cask End Impact Limiter
The attenuator is installed as the energy-absorbing core within impact limiters mounted at each end of the transport cask. The impact limiter consists of:
· Internal core: High crush strength aluminum honeycomb (this product)
· Enclosure: All-welded austenitic stainless steel or Inconel 625 skin
· Attachment: Bolted to cask body with high-strength fasteners
Proven Cask Applications:
Cask Design Honeycomb Configuration Reference
GA-4 / GA-9 Aluminum honeycomb impact limiters
FuelSolutions™ TS125 Bi-directional aluminum honeycomb (2,250 psi outer core)
HI-STAR 60 Aluminum honeycomb in stainless steel skin
NAC-STC Bi-directional corrugated honeycomb (plateau stress ≥12.35 MPa)
 
Pasia Industries, a professional advanced honeycomb core innovator and manufacturer, delivers versatile honeycomb-based products to the global market with more than 20 years of experience. The energy absorption honeycomb core can be produced based on conventional process with glue bonding or innovative process with machinery production with limited usage of special glue to obtain special performance such as high temperature resistance, chemical resistance etc. With sufficient technical know-how and experience, a wide range of standard and custom honeycomb energy absorbers for various applications are successfully delivered to clients with different cell sizes, core densities, crush strengths shapes and sizes. Aluminum honeycomb is the perfect material for energy absorption applications due to its high strength-to-weight ratio. It also has excellent moisture and corrosion resistance.
 
Specifications:
Pasia Honeycomb Energy Absorbers can be supplied based on the cell size, foil thickness and layer, aluminum grade, width and length etc. The shape and parts can be also customized as per the request from client. The crush strength can be achieved on the performance of the foil thickness and special structure.
 

 
Testing Item: Aluminum Honeycomb Plain Crushing Strength
 
Testing Data
 

Testing Curve: