NETZSCH Thermal Analysis Products and Services

Home About Netzsch Instruments Contact Us Search

Service Products Contract Testing Methods

Electro-deposition Paint

Electro-deposition coating (EDC) is widely used in the automotive industry. The importance of cathodic EDC is its ability to create an especially corrosion-resistant base coat in a single-layer process. The coating in a direct-current electrical field leads to preferential deposition of coating at corners, edges, and protrusions [W. Collong, M. Osterhold, Y.Voskuhl: Applied Rheology 1996(2) 27].

In the following, the cross-linking kinetics of a EDC is investigated. Using the results of kinetic analysis and of a simulation routine for the temperature field in a drying tunnel - a special module of CADFEM/ANSYS - the distribution of degree of reaction over the whole bodywork is predicted.

DSC Measurements

Instrument	NETZSCH DSC 204 Phoenix®
Heating rates/(K/min)	1, 2, 5, 10, 20
Atmosphere	N2; 20 ml/min
Crucible	Aluminum, pierced
Sample mass/mg	9.9 ... 10.1

The DSC measurements on freeze-dried paint material show a endothermal melting peak directly transferring into the exothermal cross-linking process.

Comparison of experiments (symbols) and calculations (black solid lines)

Temperature distribution at bodywork during the drying process.
time: 20 min

Distribution of degree of reaction of electro-deposited paint on a bodywork during the drying process.
time: 20 min

The comparison of the distribution of temperature and degree of reaction shows the correlation: at the hottest places the largest degree of reaction is predicted.
But the relation between both is not linear: the cross-linking reaction starts first at temperatures higher than 116 ¡C.

NETZSCH offers instruments for thermal analysis, thermal properties measurement, thermal hazard screening, and contract testing services. Our portfolio is the world's broadest, including a full range of dilatometers to measure high accuracy thermal expansion, classical DSC & TGA, high temperature DSC to 1650°C for specific heat, very high temperature STA (TGA-DSC/DTA) from sub-ambient to 2400°, thermal / evolved gas analysis with fully-integrated FTIR & MS, high resolution TMA and DMA, plus DEA - dielectric analysis for thermoset cure monitoring. We also feature leading-edge technology for thermal conductivity by guarded hot plate and heat flow meters, laser flash thermal diffusivity measurement, thermal hazard screening via adiabatic reaction calorimetry, as well as refractories testing including HMOR, CIC, and RUL. Finally, we offer advanced software packages including thermokinetics for process modeling and development.

Information Request Form
Home Methods Products Service

NETZSCH Group