Adolf Hitler (German: [ˈadɔlf ˈhɪtlɐ]; 20 April 1889 – 30 April 1945) was an Austrian-born German politician who was the leader of the Nazi Party (German: Nationalsozialistische Deutsche Arbeiterpartei (NSDAP); National Socialist German Workers Party). He was chancellor of Germany from 1933 to 1945 and Führer (leader) of Nazi Germany from 1934 to 1945. As effective dictator of Nazi Germany, Hitler was at the centre of World War II in Europe, and the Holocaust.
Hitler was a decorated veteran of World War I. He joined the German Workers' Party (precursor of the NSDAP) in 1919, and became leader of the NSDAP in 1921. In 1923, he attempted a coup in Munich to seize power. The failed coup resulted in Hitler's imprisonment, during which time he wrote his autobiography and political manifesto Mein Kampf ("My Struggle"). After his release in 1924, Hitler gained popular support by attacking the Treaty of Versailles and promoting Pan-Germanism, antisemitism, and anti-communism with charismatic oratory and Nazi propaganda. Hitler frequently denounced international capitalism and communism as being part of a Jewish conspiracy.
Hitler's Nazi Party became the largest elected party in the German Reichstag, leading to his appointment as chancellor in 1933. Following fresh elections won by his coalition, the Reichstag passed the Enabling Act, which began the process of transforming the Weimar Republic into the Third Reich, a single-party dictatorship based on the totalitarian and autocratic ideology of National Socialism. Hitler aimed to eliminate Jews from Germany and establish a New Order to counter what he saw as the injustice of the post–World War I international order dominated by Britain and France. His first six years in power resulted in rapid economic recovery from the Great Depression, the denunciation of restrictions imposed on Germany after World War I, and the annexation of territories that were home to millions of ethnic Germans – actions which gave him significant popular support.
Hitler actively sought Lebensraum ("living space") for the German people. His aggressive foreign policy is considered to be the primary cause of the outbreak of World War II in Europe. He directed large-scale rearmament and on 1 September 1939 invaded Poland, resulting in British and French declarations of war on Germany. In June 1941, Hitler ordered an invasion of the Soviet Union. By the end of 1941 German forces and the European Axis powers occupied most of Europe and North Africa. Failure to defeat the Soviets and the entry of the United States into the war forced Germany onto the defensive and it suffered a series of escalating defeats. In the final days of the war, during the Battle of Berlin in 1945, Hitler married his long-time lover, Eva Braun. On 30 April 1945, less than two days later, the two committed suicide to avoid capture by the Red Army, and their corpses were burned.
Under Hitler's leadership and racially motivated ideology, the Nazi regime was responsible for the genocide of at least 5.5 million Jews and millions of other victims whom he and his followers deemed racially inferior and socially undesirable. Hitler and the Nazi regime were also responsible for the killing of an estimated 19.3 million civilians and prisoners of war. In addition, 29 million soldiers and civilians died as a result of military action in the European Theatre of World War II. The number of civilians killed during the Second World War was unprecedented in the history of warfare.
Electroplating is a process that uses electric current to reduce dissolved metal cations so that they form a coherent metal coating on an electrode. The term is also used for electrical oxidation of anions onto a solid substrate, as in the formation silver chloride on silver wire to make silver/silver-chloride electrodes. Electroplating is primarily used to change the surface properties of an object (e.g. abrasion and wear resistance, corrosion protection, lubricity, aesthetic qualities, etc.), but may also be used to build up thickness on undersized parts or to form objects by electroforming.
The process used in electroplating is called electrodeposition. It is analogous to a galvanic cell acting in reverse. The part to be plated is the cathode of the circuit. In one technique, the anode is made of the metal to be plated on the part. Both components are immersed in a solution called an electrolyte containing one or more dissolved metal salts as well as other ions that permit the flow of electricity. A power supply supplies a direct current to the anode, oxidizing the metal atoms that it comprises and allowing them to dissolve in the solution. At the cathode, the dissolved metal ions in the electrolyte solution are reduced at the interface between the solution and the cathode, such that they "plate out" onto the cathode. The rate at which the anode is dissolved is equal to the rate at which the cathode is plated, vis-a-vis the current through the circuit. In this manner, the ions in the electrolyte bath are continuously replenished by the anode.
Other electroplating processes may use a non-consumable anode such as lead or carbon. In these techniques, ions of the metal to be plated must be periodically replenished in the bath as they are drawn out of the solution. The most common form of electroplating is used for creating coins such as pennies, which are small zinc plates covered in a layer of copper.
The cations associate with the anions in the solution. These cations are reduced at the cathode to deposit in the metallic, zero valence state. For example, in an acid solution, copper is oxidized at the anode to Cu2+ by losing two electrons. The Cu2+ associates with the anion SO42− in the solution to form copper sulfate. At the cathode, the Cu2+ is reduced to metallic copper by gaining two electrons. The result is the effective transfer of copper from the anode source to a plate covering the cathode.
The plating is most commonly a single metallic element, not an alloy. However, some alloys can be electrodeposited, notably brass and solder.
Many plating baths include cyanides of other metals (e.g., potassium cyanide) in addition to cyanides of the metal to be deposited. These free cyanides facilitate anode corrosion, help to maintain a constant metal ion level and contribute to conductivity. Additionally, non-metal chemicals such as carbonates and phosphates may be added to increase conductivity.
When plating is not desired on certain areas of the substrate, stop-offs are applied to prevent the bath from coming in contact with the substrate. Typical stop-offs include tape, foil, lacquers, and waxes.
Initially, a special plating deposit called a "strike" or "flash" may be used to form a very thin (typically less than 0.1 micrometer thick) plating with high quality and good adherence to the substrate. This serves as a foundation for subsequent plating processes. A strike uses a high current density and a bath with a low ion concentration. The process is slow, so more efficient plating processes are used once the desired strike thickness is obtained.
The striking method is also used in combination with the plating of different metals. If it is desirable to plate one type of deposit onto a metal to improve corrosion resistance but this metal has inherently poor adhesion to the substrate, a strike can be first deposited that is compatible with both. One example of this situation is the poor adhesion of electrolytic nickel on zinc alloys, in which case a copper strike is used, which has good adherence to both.