Sealing compounds and Sealants

Sealants are used in a wide variety of industries, such as the aerospace industry or automotive and shipbuilding. Depending on the application - e.g. in the fuel tank, for edge sealing, as interfay or overcoating - they have to meet specific requirements. Sealants must therefore be individually developed, tested, and approved. Fraunhofer IFAM has many years of practical experience in this area. The focus is on the selection of pretreatment, bonding agents, and sealants for the specific application, as well as their testing and qualification. Our institute offers support in the appropriate selection and performance of the necessary material tests.

 

From AITM2-0013 to ISO 868 to ISO 37: We offer comprehensive test and inspection methods for sealants

Constantly changing conditions such as

• Automated application in the aviation industry
• Shortening of process times through e.g. forced drying
• Availability of chemical raw materials
• New health & environmental requirements (e.g. REACH regulation)
• New areas of use & applications

repeatedly present manufacturers and users of sealants with major challenges and make modifications or reformulations of sealants and associated coating systems unavoidable. The modified or new products as well as the adapted production processes must then be tested and qualified for the corresponding areas of application. As an independent research institute, we can provide support in selecting and performing the necessary material tests. The following test methods are available for this purpose:

• Sealant adhesion by linear debonding test according to AITM2-0013
• Peel strength for sealants according to BATS 3488
• Hardness test (Shore A, D, 0, 00) according to ISO 868 and ISO 7619-1
• Tensile strength and elongation according to ISO 37
• Tensile shear test according to AITM1-0030
• Non-hardening characteristic of sealant according to AITM1-0032
• Curing rate according to AITM1-0033
• Assembly time according to AITM1-0036
• Removability test according to AITM2-0069
• Adhesion elongation according to AITM2-0070
• Galvanic corrosion prevention capability of sealants according to AITM5-0002
• Corrosion prevention capability of non-hardening jointing compounds according to AITM5-0012
• Tack free time nach AITM2-0034
• Application time nach AITM7-0003
• Tightness Test nach NASM 1312-19
• Tightness test for sealants (pressure test, in-house development)
• Dynamic sealant test (dynamic loading of sealants, in-house development)
• Media exposure according to customer requirements (water, climate, high temperatures, 3% NaCl, hydraulic fluid, kerosene, weathering...)

If required, special test methods can also be developed according to customer specifications or existing tests can be adapted.

 

For your application: material procurement, sample production and testing as well as aging and exposure in media from a single source

Due to the wide technological range of our institute, we can offer material procurement (samples), pre-treatment, coating and sample production as well as aging methods and testing from a single source. On request, we can also draw on various supplementary analysis options, for example to check the chemical composition of the sealant, to investigate the wetting behavior, the compatibility of materials (adhesion promoters, cleaners, paints, other sealants), or to investigate the interface between sealant and substrate.

 

Ongoing research projects on sealants:

We are currently working on the following projects with different topics:

"TIRIKA" (FKZ 20W2103G):

Aim: Development of REACH-compliant D4-D6 siloxane-free sealants and adhesives as well as an improved, environmentally compatible interior tank coating.

"PIRANHA" (FKZ 20Q1921B):

Aim: Development of a production-accompanying quality control system for curing sealants using ultrasonic technology.

"Quality assurance of sealants" (IGF project):

Aim: Increasing the efficiency of joint sealing using sealants by means of non-destructive inline quality assurance during the curing process.

 

Surface technology is a core competence of Fraunhofer IFAM. The "Adhesion and Interface Research" and "Paint/Lacquer Technology" departments work together on projects for the development and testing of sealants and the qualification and optimization of processes for the use of sealants. As a result of this interdisciplinary cooperation, the team from both departments has comprehensive know-how in the areas of development, testing technology, and material and surface analysis.