Max of Corner
Max of corner averaging means that the maximum value from all the corners of an element are extracted and the value is shown at the centroid of the element.
For example, as shown in the Nodal Averaging of Elemental Results topic, there are four tensors at each corner of the element A: [A1], [A2], [A3], and [A4].

This averaging option is only available when the Use corner data option is checked in the Contour or Iso panels.