KARAKTERISASI PAHAT BUBUT JENIS HSS (HIGH SPEED STEEL) PRODUK CINA DAN PRODUK JERMAN

Abstract

HSS (High Speed Steel) is a high alloy steel with primary alloying element carbon (C), tungsten (W), vanadium (V), molybdenum (Mo), cromium (Cr) or cobalt (Co). Commonly sighted types of HSS are Tungsten series HSS, Tungsten-Molybdenum series HSS, and High Performance HSS. The most important properties of HSS is cutting ability. Cutting ability depends on a combination of hardness, hot hardness, wear resistance, and toughness. In the market, there are several types of HSS cutting tool made from different countries, such as from China, Taiwan and Germany. The problem was, eventhough they have same brand and size, the price is not the same. Germany HSS cutting tool was more much expensive that one from China. The research aimed to understand the cause of the problem by determining the characteristic of HSS cutting tools made in China and Germany, especially on hardness, micrography and chemical composition test. The specimens were BOHLER RAPID EXTRA 1200 with ¼” X 4” on size made from China and Germany. The result showed that China HSS cutting tool has 62,17 HRC on hardness, containing martensite and retained austenite on microstructure. Germany HSS cutting tool has 64,42 HRC on hardness, containing martensite and carbides on microstructure, and more W, V, and Mo elements on chemical composition. The study concluded that HSS cutting tool Germany product has better quality than China product. Keywords : HSS, hardness, microstructure, chemical composition and cutting ability.