Application-specific Sample Holders

The DMA 242 C covers anextremely broad range of sample geometries. Through the use of relatively largesamples (max. sample length60 mm in the bending mode), an excellent extra- polation of the results to component parts is achieved. By using a container, measu- rements in liquids are possible(immersion tests). Select theideal sample holder* for your particular problem: Three-point Bending The sample is supported ontwo edges, while the cuttingend of the push rod applies a load to the sample from above. The spacing between the two edges is in accord- ance with DIN53457. Four different free bending lengths between 10 and 50mm are available. This de- formation mode is ideal for materials with a high stora- ge modulus such as filled or reinforced thermoplastics and thermosets (composi- tes) or metals and alloys. Dual Cantilever Bending The ends of the sample are between 2 and 32 mm areavailable. By leaving oneend of the sample free, tightly clamped. This arrange- ment is especially suitablefor samples of mid modulus range (rubber and thermo- plastics). Holders for three measurements can be made in the single cantileverbending mode as well. different bending lengths Compression The sample (rubber, foams,biopolymers, pasty materials,etc.) is placed on a flat sur-face in the sample holderand pressure is applied from above with the plate-shapedend of the push rod.Different diameters up to30 mm are available. Byusing a ceramic disk and a
push rod of fused silica, asmall temperature gradient can be achieved (especially for foams and rubber). If the end of the push rod is pointedrather than flat, the term is penetration . For example,this type of stressing is suita- ble for the investigation ofcoatings. Linear Shearing Two identical samples arepressured or glued in sand- wich geometry between the flat surfaces of the sampleholder and the push rod.The load is applied via the plate like extension of thepush rod. Two types of sample holders are espe- cially suited for soft materials such as rubber and adhesives. Tension The tension mode is prefer-able for the measurement offilms and fibers or thin rubber samples. The lower end of the sample is held inplace, whereas the upper end is clamped to the oscillating push rod.5
* special deformation modese.g. for viscous liquids or very stiffsamples upon request