Dry sliding adhesive wear behaviour of as-cast and austempered ductile iron (ADI) samples alloyed with manganese and copper was investigated in a pin-on-disc wear testing machine. As-cast samples suffered a rapid and continuous wear, while the austempered samples exhibited improved wear resistance on increasing the austempering temperature and time. ADI samples with higher copper plus manganese contents inherently possessed higher hardness due to presence of martensite in the ausferrite matrix. The wear conditions used in the present
study further promoted the formation of martensite under wear load and contributed much improved wear performance. In ADIs containing manganese only, wear process involved a mixed mechanism of oxidation and delamination. On combined alloying with copper and manganese, wear resistance increased considerably showing only mild oxidation and practically no delamination. The combinedly alloyed austempered samples exhibited even better wear resistance than that of cast and heat treated high manganese steel. Thus, the addition of manganese and copper in the experimental ductile irons assisted austempering by virtue of their synergistic effect on hardenability of Fe-C alloys and improving wear resistance through subsequent work hardening of the wear surface.

Steel enjoys an unsurpassed wide range of properties: first of all its stiffness-strength-formability relationship contributes to featuring steel a high potential as versatile light-weight construction material. In this respect it pays to use steel, its price cannot be undercut without accepting compromises. This is topped by additional gains comprising high availability, reliability, excellent manufacturability and recyclability. Steel enjoys great popularity amongst designers, most of them are very familiar with it. In intermaterial competition, steel may not win in every single discipline, but steel is the undisputed champion in multi-discipline jobs. This makes steel an indispensable material.

High nitrogen steels are commonly known for their excellent mechanical properties, i.e. strength and corrosion resistance. A state-of-the-art production routine is P-ESR melting (pressurised electro slag remelting). It is possible to manufacture both, austenitic as well as martensitic steels suitable for forging and hot rolling. Some basic knowledge of the material peculiarities is mandatory to avoid any potential issues during plastic deformation. The following paper provides an overview of the manufacturing of HNS as well as some properties to be considered for plastic deformation.

Corrosion behavior of 19Cr-18Mn-0.69N austenitic stainless steel was studied by cyclic polarization technique in 3.5 % NaCl solution and was compared with that of other austenitic stainless steels having different compositions namely, AISI 316L and one with 14 Cr and  8% Mn, denoted 14Cr-8Mn in the following. The results showed that 19Cr-18Mn-0.69N austenitic stainless steel exhibits higher pitting resistance compared to that of other two alloys. SEM micrographs of 19Cr-18Mn-0.69N austenitic stainless steel after corrosion showed no pits at the alloy surface even when it was polarized beyond transpassive pitting potential. However severe attack was seen at the araldite-metal interface. But, in case of AISI 316L and 14Cr-8-Mn severe pitting attack was seen at the surface, whereas no attack was seen at araldite-metal interface. Critical crevice temperature for the three stainless steels was determined. 19Cr-18Mn-0.69N austenitic stainless steel was found to have good crevice corrosion resistance compared to other alloys investigated.

The total amount of solid particles as a parameter influencing the viscosity and the foaming properties of the slag was investigated. In this context, the amount of these particles for different process conditions was quantified. In addition, the effect of the process conditions on the total amount of the particles was studied. More specifically, some parameter studies were carried out in oder to determine the influence of chromium oxide (Cr2O3) content, calcium oxide (CaO) content, basicity and temperature on the total amount of solid particles. The interactions between the process conditions were also taken into account.

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Perfectly matched value adding system that fulfills the requirements of the chemical industry

ACHEMA visitors will observe the function of the system using both steel and plastic drums in a simulated circuit. An automatic labeler perfectly rounds out the simulation. A video will also demonstrate in an entertaining way how the process connection with SAP works.

ANDRITZ delivers new walking beam furnace for wire mill at Swiss Steel AG

International technology group ANDRITZ has received an order from Swiss Steel AG, Switzerland, for the supply, installation, and startup of a new walking beam furnace with an output of 150 t/h for heating the continuous-cast billets at the Emmenbrücke plant, Switzerland. Start-up is scheduled for the fourth quarter of 2019.

Saarstahl AG and Mapudo GmbH are presenting themselves together for the first time at the "Wire"

Start-up Mapudo is the new “online wire” connection to Saarstahl

· Source 2A material easily using the platform mapudo.com

· Joint presentation in hall 12 at stand A 72

Expansion: GFH GmbH increases office and production space

Since the laser micro machining specialist GFH has grown continuously at an average rate of 50% over the last few years, a decision was made in the spring of 2016 to increase production capacities and expand at the Deggendorf location.