HONEYCOMB SANDWICH DESIGN TECHNOLOGY

MECHANICAL ENGG.

(4TH YEAR)

HONEYCOMB SANDWICH DESIGN TECHNOLOGY

INTRODUCTIONMATERIALDESIGNMANUFACTUREAPPLICATIONS

INTRODUCTIONHoneycomb structures are natural or man-made structures .The cells are often columnar and hexagonal in shape.The strength of laminated or sandwich panels depends on the

size of the panel.The material takes its name from its visual resemblance to a

bee's honeycomb - a hexagonal sheet structure. The core resists the shear loads, increases the stiffness of the

structure.

MATERIALThe following criteria should be considered in the routine

selection of core, facing, and adhesive.In Structural Considerations such as strength, stiffness,

adhesive performance, economical consideration.In Environmental Considerations such as temperature, Heat

Transfer, Flammability, Moisture/Humidity.In Mechanical Performance we consider cell size, cell shape,

skin materials, adhesive materials.Generally we use material for honeycomb core is graphite

polyimide, aluminium, glass polyimide, polyurethane foam.

DESIGN

LOADS: The applied load creates a bending moment which is a maximum at the fixed end, and a shear force along the length of the beam.

DEFLECTIONS: The bending deflection is dependent on the relative tensile and compressive module of the skin materials.

The shear deflection is dependent on the shear modulus of the core.

Total Deflection = Bending Deflection + Shear Deflection

FAILURE MODES

Designers of sandwich panels must ensure that all potential failure modes are considered in their analysis.

Strength

• Stiffness

Panel buckling

• Shear crimping

Skin wrinkling

• Intra cell buckling

MANUFACTURE

Basic Honeycomb Sandwich Production Methods

Heated Press, generally used for the production of flat board or simple preformed panels.

Vacuum Bag Processing, used for curved and complex form panels.

Matched Mould Processing, used generally for batch production of finished panels

Heated Press

Vacuum Bag Processing

Matched Mould Processing

APPLICATIONS

Aerospace

Aeronautical

Naval

Automobile Etc.

Aerospace

1. Fairings: Carbon prepregs. Aluminium honeycomb and adhesives.

2.External Payload Carrier Assembly(SPELTRA): Carbon prepregs, aluminium honeycombs and adhesives.

3.EPS Ring: Epoxy/carbon prepreg or RTM.

5.Booster Capotage: Epoxy glass/non-metallic honeycomb.

6.Yoke: Epoxy carbon filament winding .

Aeronautical

1.Radar Transparent Radome: Epoxy or BMI Prepreg or RTM resins And woven preforms (socks).

3.Fuselage Panel Sections: Epoxy carbon Prepregs. Non-metallic Honeycomb core and Redux adhesives.

10.Flying Control Surfaces: Epoxy carbon and glass Prepregs. Honeycomb Core material and Redux adhesives.

Naval2.Hull Skin Structure: Prepregs,

engineered fabrics, honeycombs.

4.Suspended Ceilings: Lightweight sandwich panels/honeycombs.

7.Accommodation Cabin Units: Lightweight sandwich panels, Prepregs and honeycombs.

9.Weather Shield: Prepregs and honeycombs.

10.Communications Equipment: Prepregs and honeycombs.

AutomobileChassis of Ferrari F50:

Nomex honeycomb core, sandwich construction.

Chassis of DOME F150: Carbon fibre/ aluminium honeycomb sandwich  monocoque.

Bluebird-Proteus CN7: Advanced aluminum 

honeycomb sandwich of immense strength.

THANK YOU