Effect of heat treatment on microstructure and erosion. Autonomous san luis potosi university, san luis potosi, mexico. Our concern for the rest of this paper, however, will be with hard chrome plating. Colour metallography of cast iron by zhou jiyang, professor, dalian university of technology, china. Highchromium 2234 per cent cast iron alloys and their simulated behaviour at the sugar industry e zumelzu, 0 opitz and c cabezas. Nihard abrasion resisting white irons bs 4844 1986. Hard chrome is used as a wear resistant coating not only on steel but. Referring to figure 2, liquid steel flows out of the ladle 1 into the tundish 2, and then into a watercooled copper mold 3. Wear resistance of nihard 4 and highchromium cast iron. Melting practice of nonferrous alloys of al, cu, mg, zn and ni, refining, deoxidation, degassing and grain refinement treatments. The term for force per unit of area stress is the newton per square meter nm 2. Heat treating of highalloy white irons total materia article.
The samples used for microstructural analysis, crystalline phases identification and hardness measurement were machined to disk shape height 20 mm, diameter 35 mm. Variations in the chromium to carbon ratio will provide fluctuating matrix structures from martensite to austenite. Mastering photographic composition, creativity, and. We offer our client an excellent quality range of ni hard castings, which are manufactured from high grade quality raw materials.
Nihard cast components can extend the life of parts and products, providing longer use, when compared with other cast iron techniques. Influence of nb, v and ta on the microstructure of ni hard type cast iron for hot steel strip mills sergio villanueva b. The ascast hardness is typically 500 bhn depending on the section thickness of the casting. Hard chrome is used as a wear resistant coating not only on steel but also on a wide variety of other metals. The nickelchromium irons are also commonly identified as ni hard types 1 to 4. Specific targets will vary, depending on bar size, although the ranges listed are required. Nihard castings, also written as nihard castings, are extremely wear resistant castings ideal for abrasive resistant products and components. Mastering photographic composition, creativity, and personal. Highchromium 2234 per cent cast iron alloys and their. Apr 04, 2016 astm a532 class ii type b high chromium alloy the 15%cr alloy is typically poured on request at penticton foundry. The corrosion resistance of nickel 200 makes it particularly useful for maintaining product purity in the. Pdf control of carbides and graphite in nihard type.
With the lower cr and an addition of molybdenum, this alloy is used in operating environments where abrasion and impact are the wear mechanisms. Stourvale road, lye, stourbridge, west midlands dy9 8pr telephone. I, type b, such as ni hard 4 but excels in corrosion resistance over this class of irons. Astm a532 class i type a nihard 1 high chrome white iron. Balance average hardness 300 hbn 800 hbn white iron maxalloy 5 maxalloy 2 maxalloy 5a nihard 4. Mastering photographic composition, creativity, and personal style alain briot. Properties and applications of ni resist and ductile ni resist alloys general characteristics of the ni resist austenitic cast iron alloys there are two families of ni resist austenitic cast irons. The dominating factors are the chemical composition and the structure of the matrix. The reader is cautioned that silicon and other alloying elements may considerably change the maximum solubility of carbon in austenite y. Here youll find current best sellers in books, new releases in books, deals in books, kindle. Heat treatments of castings, shop floor melt quality tests. Words of blessing are written on red paper, called ch. This kind of cast iron is a balanced composition of carbon, nickel, chromium and silicon. At the end of heat treatment, samples were always cooled down in calm air.
Influence of niobium and vanadium on the microstructure of ni. Im pretty sure my direct links are being marked as spam. Comparison of three nihard i alloys conference osti. Hard chromium differs from decorative chromium not only because of. Therefore, in exceptional cases, alloys with less than 2 % c can solidify with a eutectic structure and therefore still belong to the family of cast iron. It was carried out using destabilization and sub critical heat treatment at. Highstrength lowalloy steels include many standard and proprietary grades designed to provide specific desirable. Astm a532 class ii type b chrome white iron data sheet.
On chinese new years eve, all family members return to the family house to have a feast called ni ny8f0n. Influence of niobium and vanadium on the microstructure of. Chemical composition of durabar 202 ni resist the chemical composition for durabar 202 ni resist is shown in table 1 below. Jun 15, 2016 ni hard 1 should also be considered if there are low or medium dynamic stresses. D liu jincheng, fellow of institute of cast metal engineers, uk note. Standard specification for abrasionresistant cast irons. Properties and applications of niresist and ductile ni. The three distinct groups of the alloyed cast irons, which have enhanced heat and corrosion resistance for specific environment, are 1. Ni hard 1 should also be considered if there are low or medium dynamic stresses. These are the standard or flake graphite alloys and the ductile or spheroidal graphite alloys.
Chromium is the hardest of the most commonly deposited metals. Heat treating of highalloy white irons total materia. Kassim, alrubaie and michael pohl 8 investigated the heat treatment and two body abrasion of ni hard 4 cast iron. Since this can be a large number, the prefix mega is used to indicate 1,000,000 units and the term meganewton per square meter mnm 2 is used. Table 53 lists the chemical composition of ni hard. Control of carbides and graphite in ni hard type cast iron for hot strip mills article pdf available in materials science forum 561565 january 2007. Pdf heat treatment and twobody abrasion of nihard 4. Here youll find current best sellers in books, new releases in books, deals in books, kindle ebooks, audible audiobooks, and so much more. The books homepage helps you explore earths biggest bookstore without ever leaving the comfort of your couch.
Its important to note that only rexnord designs and manufactures all critical components used in our elevators. Workpiece material category examples low carbon composition of durabar 202 ni resist the chemical composition for durabar 202 ni resist is shown in table 1 below. Rexnord high performance bucket elevators are designed speci. These ni hard castings are widely known for its durability and quality. Hc28 owes its abrasion resistant properties to the various chromium iron carbides in the microstructure.
Nickelchromium white irons one of the oldest groups of highalloy irons of industrial importance, the ni cr white irons, or ni hard irons, have been produced for more than 50 years and are very costeffective materials for crushing and grinding. Although ni hard cast iron and highchromium cast iron appeared almost at the same time, hcci was well developed in the 1960s and 1970s. Small quantities of chromium, nickel, molybdenum, copper, nitrogen, vanadium, niobium, titanium, and zirconium are used in various combinations. The carbon low alloy steel casting is manufactured using the latest technology which makes it perfect for surface hardening. This book updates information for users on nihard s material data and applications. These alloys may be made by melting process and shall have microstructures that consist of carbides, martensite, bainite, austenite, and in exceptional cases, minor amounts of graphite or pearlite. Metallurgical aspects of highchromium white irons prof. Nickelchromium white irons the oldest group of highalloy irons of industrial importance, the nickelchromium white irons, or ni hard irons, have been produced for more than 50 years and are very costeffective materials for crushing and grinding. Colour metallography of cast iron by zhou jiyang, professor, dalian university of technology, china translated by ph. These are four digit numbers which represent chemical composition standards for steel specifications. Cast materials at a glance description material material chemical composition reference values, wt. Hc28 high chrome white iron home townley engineering. These nii hard castings can be customized as per our valued customers specifications. Control of carbides and graphite in ni hard type cast iron for hot strip mills article pdf available in materials science forum 561565 january 2007 with 450 reads how we measure reads.
Ni hard 1 is the least expensive wear material, but over the last 10 years many users of this material have been changing to astm a532 class ii and iii materials. By varying composition and heat treatment, these properties can be. We manufacture all types of ni hard casting grade 1, 2. Technical information workpiece material categories. Its microstructure consists of carbides and mainly martensitic matrix. Chapter 1 introduction, chapter 2 grey iron, chapter 3 spheroidal graphite cast iron, chapter 4 vermicular cast iron, and chapter 5 white cast iron. With specific heat treatments it is possible to achieve a high hardness for. Ni resist type 2 will be similar to type 1 having an austenitic matrix with approximately 510% alloy carbide. Solidification begins in the mold, and continues through the first zone 4 and strand guide 5. This specification deals with abrasionresistant cast irons used for mining, milling, earthhandling, and manufacturing industries. Mastering photographic composition, creativity, and personal style by alain briot. Chapter 1 introduction, chapter 2 grey iron, chapter 3 spheroidal graphite.
Astm a532 class ii type b high chromium alloy the 15%cr alloy is typically poured on request at penticton foundry. B75 2009 771dc22 2009003899 distributed by oreilly media 1005 gravenstein highway north sebastapool, ca 95472. Pdf control of carbides and graphite in nihard type cast. From wikipedia, the free encyclopedia the society of automotive engineers sae designates sae steel grades. Ni hard is the generic name for a family of white cast irons alloyed with nickel and chromium to give high hardness and outstanding resistance to abrasion.1258 239 929 138 34 732 1339 729 32 1398 1312 668 1501 465 226 737 1430 336 1166 208 1000 78 313 865 886 540 928 152 593 664 920 1455