Flat absorbers made of microperforated
Noise emissions are an important
issue for automobile manufacturers, on one hand, they are
legally required to comply with low limit values, and on the
other, acoustic insulation increases the comfort of vehicle
occupants, and thus serves as a sales argument. When
choosing an absorber system, outstanding insulating and
mechanical material properties play a decisive role for the
manufacturers, but increasingly often so does available
space. Sekisui Alveo, manufacturer of polyolefin foams, has
optimized the acoustic properties of its products through
modification and special treatment. The new flat absorber
made of micro-perforated Alveocel foam efficiently reduces
noise emissions in the engine compartment and meets the
need of the automobile industry for space-saving solutions.
Already for years, Sekisui Alveo has been closely collaborating
with systems suppliers to develop various efficient box absorber
solutions. Due to the thermal requirements, only highly resistant
PP foams come into question for applications in the engine
compartment foams that possess extended temperature
resistance of over 140 °C. With its new foam Alveoce l, the
company has now developed an especially space-saving variant:
a flat absorber made of micro-perforated foam.
Perforation instead of thermoforming
The Alveocel foam is needled in a specific pattern and thereby is given its acoustical
function. The acoustic waves penetrate the partially open cells
after perforation. There they are on one hand transformed into kinetic energy (Helmholtz resonance effect), and on the other into heat energy by friction (dissipation). Through the combination of the two effects, the flat absorber covers a wide frequency range. Even a single-layer micro-perforated absorber efficiently reduces noise emissions from the engine compartment. The absorptive effect is increased by the use of several foam layers.
About Sekisui Alveo AG
Sekisui Alveo AG with head office in Lucerne, Switzerland, develops and
produces extruded and cross-linked polyolefin foams, which are used in:
Adhesive Coating, Automotive, Construction including Artificial Turf as well as
Industrial and Consumer Goods. The solutions are developed in close
cooperation with processing companies and manufacturers, and tested and
approved in the company's Application Services Laboratory.
Sekisui Alveo was established in 1971 and today employs 500 people in 12
countries. Beside the head office in Lucerne and the three production plants in
Roermond (Netherlands), Bad Sobernheim (Germany) and Merthyr Tydfil (UK)
the company has local offices throughout Europe and in South America.
Source: Sekisui Alveo AG