The tōn fluẍ®  products in the Lydall fluẍ thermal and acoustical shields product family are heat shields with marked acoustic properties that help reduce noise at the source. The acoustic performance is generated through the mixing of several materials and focuses on mid-range frequency noise absorption.


  • Single Layer – Micro Pierced or Perforated
  • Single layer of aluminum or thin gauge steel
  • Open area generally < 4%
  • Multiple options for piercing and perforating
  • Standard piercing patterns below

Holes / cm2

Metal Thickness, mm

L16 < 0.50 mm
L24 < 0.40 mm
L45 < 0.15 mm
  • Multi Layer
  • Combines perforated or pierced metallic layers with an intermediate layer of fiber or air
  • The intermediate layer dictates the shield “Gap”
  • Examples below with high temperature fiber

Open Area

Gap Thickness

Target Frequency

3% 4 mm 4400 Hz
1.5% 12 mm 2000 Hz
22% 10 mm 6300+ Hz

Acoustical Performance

  • Focus on noise absorption to reduce the overall sound pressure level of the vehicle – cabin and drive-by
  • Mix of all metal or metal and fiber materials; material selection is pinned to the application temperature and operating environment
  • Metallic layers are pierced or perforated to a pattern designed to absorb noise across a specific frequency range

Mechanical Performance

  • Hemmed edges for handling safety and increased product robustness
  • Roll and plate embossment provides an increase in part rigidity
  • Wide array of approved and commonly used alloys available to exceed the requirements of harsh thermal and mechanical environments

Environmental Performance

  • Fully recyclable – single layer or double layer air products
  • Raw material is comprised of 80% recycled material
  • All alloys resist exposure to common automotive fluids
  • All alloys resist long-term exposure to corrosive environments