This thesis investigates the existence and form of association between the technological structure of one of the most highly capital-intensive industries in the world, the paper and pulp (p&p) industry, and its dynamic behaviour in terms of market growth and development. Industrial structure issues are particularly relevant in highly capital-intensive sectors because they reflect the influence of economies of scale and changing patterns of entry and exit. The thesis draws upon two related bodies of literature: the dynamics of industrial structure, and heterogeneity within industry. It uses a quantitative hypothesis-deductive method and two panel databases. The first of these databases identifies key characteristics of the world's 150 largest p&p firms during the period 1978-2000, accounting for two-thirds of world output. The second dataset contains annual production capacity for the entire population of US p&p companies during the period 1970-2000. The US is the largest producer and consumer of p&p, accounting for one-third of world output. The main findings are as follows. Firstly, we demonstrate that p&p firms' growth is not a 'random walk' process, a generalization referred to in the literature as Gibrat's law. Nor is there a linear relation between growth and size distribution or between time and growth rates. We find that size, technology and time matter. Secondly, we demonstrate that this departure from Gibrat's law is due to the existence of three distinctive technological configurations or strategic groups of firms: 'Large & Diversified', 'Medium & Specialized', and 'Small & Very Specialized', which show persistently heterogeneous growth performance. In contrast with the findings in most of the recent empirical literature that shows smaller firms growing faster within the industry size distribution, the medium & specialized p&p companies show systematically the highest rates of growth. Thirdly, patterns of p&p firm survival and technological adoption behaviour over the last three decades are identified and related to the principal technological advances during the period, i.e. the very rapid increase in paper machine operating speed. The research contributes to the literature by providing robust new empirical evidence of the persistence over time of an intra-industry technological structure that systematically influences the heterogeneous performance of firms with different technological configurations and whose origins are linked to firms' growth processes (industrial dynamics) in the p&p industry.

In der Bereichsbibliothek Dre•punct der SLUB Dresden wird in Kooperation mit dem Lehrstuhl für Technik- und Technikwissenschaftsgeschichte der TU Dresden bis Oktober 2010 die Ausstellung „Papiergeschrei – Ein Material für alle Fälle“ zu sehen sein. Auf dem Tresen, dem Schreibtisch und in der Küche wird gezeigt, was man mit dem „Alleskönner“ alles machen kann.

Hot cracking is a serious problem that encounters during welding of aluminium-magnesium alloys. In the present study, solidification and liquation type of hot cracks in weld metal and the heat-affected zones of 5086-H32 aluminium alloy were investigated by using Modified Varestraint Test (MVT) with TIG-AC and TIG-DC welding. With determining the size, type and number of cracks, a relation was established between welding line energy and strain on the hot crack formation. This information was used to determine the hot crack safe parameter ranges. The hot cracking tendency as a function of applied parameters were discussed in the frame of temperature fields around the moving heat source. Moreover, the characteristic hot crack locations on the 5086-H32 MVT specimens were generalized. The results of the study indicated that the increase in line energy and strain increased the hot cracking tendency of the specified aluminium alloy. In the low line energy range, the main hot cracking mechanism is the solidification cracking which could be overcome by the use of a suitable filler material. At high line energy range, due to the increased amount of interdendritic liquid, the amount of solidification cracking decreases by healing mechanism. However, because of the enlarged-temperature-field around the weld zone, fraction of HAZ cracking increases. The comparison between the hot cracking tendencies in low and high line energies indicates that the low line energy ranges with low augmented strains resulted in hot crack safer parameters.

In der Bereichsbibliothek Dre•punct der SLUB Dresden wird in Kooperation mit dem Lehrstuhl für Technik- und Technikwissenschaftsgeschichte der TU Dresden bis Oktober 2010 die Ausstellung „Papiergeschrei – Ein Material für alle Fälle“ zu sehen sein. Auf dem Tresen, dem Schreibtisch und in der Küche wird gezeigt, was man mit dem „Alleskönner“ alles machen kann.