ABSTRACT Friction stir welding (FSW) of high-strength steels shows promise over traditional fusion welding methods because it is an autogenous solid-state process with low heat input. Technical and financial requirements for the tool and welding machine can become limiting with increasing plate thickness and 2-sided welds are an option. It can also result in better mechanical properties. Low-alloyed low-carbon high-strength complex phase steel was friction stir welded to investigate the difference in microstructure and mechanical properties between 1-sided and 2-sided welds and compared them to the base material and fusion welding methods. The 2-sided welds achieved tensile properties comparable to fusion welding methods and about 85 % of values for the base material. Only the 1-sided specimen with lack of penetration in tension failed the bending test. Second pass mostly increased the properties in the plastic region but elastic properties improved only slightly.

This paper examines paradoxes involving coronal specification. Although several phonological phenomena such as place assimilation, insertion and deletion argue for coronal underspecification, other facts like morpheme structure conditions demand coronal specification. This paper shows that this problem can be solved with the markedness hierarchy which ranks coronals low under Correspondence Theory. The hierarchy also accounts for the distributional bias of coronals in word clusters without appealing to Yip's Cluster Condition and coronal underspecification. 1.