Mechanical Analysis
Typical questions
- Strength of a batch of glass produced in a special manufacturing process
- Comparison of the strength of glasses with different processing methods
- Probability of failure of glass or glass products under mechanical stress
- Decrease in strength after climatic stress
- Analysis of the cause of breakage in glass products (monolithic, composite, also in combination with other materials, e.g., metal)
- Hardness of bulk material, stiffness, and elasticity of glass
- Hardness, stiffness, and elasticity of layers on glass and other materials
- Delamination of layers under mechanical stress and/or after climatic stress
- Geometric measurement of holes in glass sheets, outer contours of glass products
- And much more
Special features of brittle materials
When subjected to stress, brittle materials always fail at the most critical defect ("weakest link"), their strength being essentially determined by the surface quality. Each individual sample therefore exhibits individual resistance to stress. To be able to make a statement about the strength of a glass with a specific processing and manufacturing condition, a statistical number of equivalent individual samples must be tested. The individual results are "translated" into a strength result for the batch using statistical methods.
These tests are usefully supplemented by a subsequent fracture analysis, which determines the position of the fracture origins and, in the best case, also the cause of the fracture.
Interpreted by experts with years of experience, the combination of strength testing and fracture analysis can provide comprehensive information, e.g., about possible pre-damage in a production line or during handling.
Fractography (fracture analysis) is also a scientifically sound method for determining the causes of a fracture in individual samples and obtaining information about at which point in the process (manufacturing, transport, other processing) a fracture-causing defect occurred.
Brittle materials also behave differently from ductile materials when determining mechanical parameters such as hardness (Vickers, Knoop, Universal hardness), plastic/elastic parameters (stiffness, elastic component) and in their reaction to scratching events. Crack formation and crack propagation influence the measurement results. Stresses introduced by indentation or scratching are stored and released again through crack formation. Ambient humidity is a determining factor in this process.
Methods in detail
Strength testing with universal testing machines
Procedures
For special tasks and sample formats outside the scope of the standards, we develop tailored strength testing methods. This includes the precise recording of the task, the development of a proposed method, the preparation of the required sample holders, the creation of a test sequence on the machine, the test, the evaluation of results, the interpretation, and the creation of a test report. Many sample formats can be tested based on the standards within the scope of accreditation. Please contact us for clarification.Applications
- Ring-on-ring test according to ISO 1288-5
- 3-point, 4-point test according to DIN EN 843-1
- Burst pressure test according to ISO 7458
- Tensile and compression tests on brittle materials, plastics, and composites using universal testing machines
Fractography (fracture analysis)
Procedures
Fractography involves analyzing fracture surfaces or broken components to understand the causes and mechanisms of the fracture. This can be used to determine at which point in the process (manufacturing, transport, other processing) a fracture-inducing defect occurred. In combination with strength tests, our experts can also make valid statements about, for example, possible pre-existing damages caused in a production line or during handling.Applications
- Fracture cause analysis on parts made of glass, glass ceramics, ceramics, and (brittle) plastics in accordance with DIN EN 843-6 and ASTM C1256
Mechanical parameters
Procedures
Mechanical parameters such as hardness (Vickers, Knoop, Universal hardness) and plastic/elastic parameters (stiffness, elastic component) and the reaction to scratching events are determined by indentation measurements. The significance of these parameters is interpreted by our specialists and designed for the specific application.Applications
- KIc of glasses and glass ceramics according to the bridge method (ASTM C 1421, SEPB)
- Microindenter: Vickers hardness, Knoop hardness, Universal hardness (Martens hardness), stiffness, elastic component, crack initiation load on bulk material
- Nanoindenter: Universal hardness (Martens hardness), stiffness, elastic fraction of layers
- Scratch behavior on bulk materials, delamination of layers
Geometric measurement
Procedures
Bei der geometrischen Vermessung mittels Koordinatenmessmaschine werden die geometrischen Eigenschaften von Objekten präzise bestimmt. Dies erfolgt durch die Messung von Koordinatenpunkten auf der Oberfläche eines Objekts, berührend oder berührungslos. Dazu werden auch für komplexe Bauteile mit schwierigen Oberflächen eigene Messstrategien entwickelt.Applications
- Measurement of microstructures in glass wafers
- Measurement of the outer contours of pharmaceutical products made of glass and plastic
Our methods of mechanical analysis
- Surface strength: Ring-on-ring measurement according to ISO 1288-5 (accredited)
- 4-point bending according to DIN EN 843-1 (accredited)
- 3-point bending according to DIN EN 843-1 (accredited)
- Surface strength using the 4-ball method
- Tensile strength (adapted to product)
- Compressive strength (adapted to product)
- Burst pressure test according to ISO 7458 (accredited)
- Fracture analysis on broken parts according to DIN EN 843-6 and ASTM C1256 (accredited)
- KIc (fracture toughness) according to DIN EN ISO 15732 or ASTM C1421
- Vickers hardness analogous to DIN EN ISO 6507-1 or ASTM C1327
- Knoop hardness according to DIN ISO 9385
- Martens hardness analogous to DIN EN ISO 14577-1
- Plate modulus (penetration modulus) analogous to DIN EN ISO 14577-1
- Elastic fraction eta analogous to DIN EN ISO 14577-1
- CIL (crack initiation load)
- Contact angle measurement according to DIN EN ISO 19403-3
- Surface energy according to DIN EN ISO 19403-2
- Microcrack depth
- Scratch behavior bulk (loaded with Knoop indenter)
- Adhesion strength of coatings (loaded with ball)
- Wear tests - Determination of friction coefficient
- Climate storage
- Dimensional measurement using coordinate measuring machine
Highlights
Our approach
Our experts at SCHOTT Analytics look forward to hearing from you. We will work with you every step of the way, from your initial inquiry to the successful resolution of your issue, no matter how challenging it may be.
Contact our experts
Whether you want to develop innovative products or ensure compliance with regulations in regulated industries, the expertise of the accredited SCHOTT laboratory ensures your success through measurable excellence.
Inge Burger