10.1 INTRODUCTION

We have categorized dimensional stability as being dependent on six major variables. These are: stress ( ?) Chapter 3; temperature ( T) Chapter 4; moisture or solute content ( M) Chapter 5; Radiation ( R) Chapter 6; time ( t) Chapter 7; and internal damage state ( D) Chapter 9. These six ( n = 6) variables can be combined into 2 ⁿ⁺¹/2 or 54 different combinations. Table 10.1 lists the book sections where combinations are covered/discussed. Some combinations are covered indirectly throughout the present book. An example is ? ? T ? D. Other variables are very difficult to study, such as t ? D, or damage development with no stress and constant conditions. Certain combinations (especially radiation effects on dimensional stability) represent excellent topics for research. The general science of hygrothermoelasticity is a start at discovering the complex interactions possible. Emphasis here, will be placed on our knowledge of possible effects of combined variables on dimensional stability.