Characteristics of ADI Ductile Cast Iron with Single Addition of 1.56% Ni

Abstract

The results of examinations of microstructure and an analysis of its impact on selected mechanical properties of austempered ductile iron (ADI) were presented in the paper. The ADI was produced from the ductile iron containing 1.56% Ni only alloying addition. The effect of the austempering time and temperature on the microstructure and mechanical properties of the examined cast iron was considered. Constant conditions of austenitizing were assumed and six variants of the austempering treatment were adopted. The studyof mechanical properties included a static tensile test, Charpy impact strength test and Brinellhardness measurement.This work complements the knowledge about alloying additions effect on microstructure and mechanical properties of ADI and focuses on the impact of a single alloying element (Ni).

Artificial Neural Networks for Producing a Low-Cost Austempered Ductile Iron

“…Figure 7a shows the graphite nodule, stabilized austenite, and acicular ferrite, as likewise seen by other authors 52,53 . Thus, in this way, our outcomes agree well with related studies on ADI 10,52,53 . Figure 7b presents SEM imaging analysis detailing the results shown in the OM.…”

“…Thus, austempering process consists of austenitising at 815-925°C to generate an austenite microstructure (γ), followed by quenching at 260-400°C for the process to occur 5,6 . The resulting microstructure is acicular ferrite, which might be called ausferrite in a carbon saturated austenite matrix [7][8][9][10] .…”

Mathematical Model of Bainitic Transformation in Austempered Ductile Iron

“…The results of calculations presented in the paper were obtained for a constant austenitization temperature, since the experimental studies presented in [15,16], which served as a basis for the verification, used only one austenitization temperature. In the model it is possible to change this parameter in the range of 820 ÷ 950 ℃, but it does not really affect the TTT graph obtained by calculations.…”

“…GS is a number of austenite grain size according of ASTM scale. Dilatometric studies and TTT diagram developed for the examined cast iron were discussed in [15]. Based on this diagram, 18 heat treatment variants have been planned.…”

“…Based on this diagram, 18 heat treatment variants have been planned. A detailed description of these studies and an analysis of the effect of heat treatment parameters on the microstructure and progress in austenite -ferrite transformation are presented in [16,15].…”