XPS and Electron Microscopy Study of Oxide-Scale Evolution on Ignition Resistant Mg-3Ca Alloy at Low and High Heating Rates

AbstractEarlier work by the authors suggested that the formation of molten eutectic regions in Mg-Ca binary alloys caused a discrepancy in ignition temperature when different heating rates are used. This effect was observed for alloys where Ca content is greater than 1 wt%. In this work, the effect of two heating rates (25 °C/min and 45 °C/min) on the ignition resistance of Mg-3Ca is evaluated in terms of oxide growth using X-ray Photoelectron Spectroscopy. It is found that the molten eutectic regions develop a thin oxide scale of ~100 nm rich in Ca at either heating rate. The results prove that under the high heating rate, solid intermetallics are oxidized forming CaO nodules at the metal/oxide interface that eventually contribute to the formation of a thick and non-protective oxide scale in the liquid state.

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Review 2: XPS and Electron Microscopy Study of Oxide-Scale Evolution on Ignition Resistant Mg-3Ca Alloy at Low and High Heating Rates

10.1017/exp.2020.41.pr2 ◽

2020 ◽

Author(s):

Yuan Chunmiao

Keyword(s):

Electron Microscopy ◽

Oxide Scale ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Heating Rates ◽

High Heating ◽

Scale Evolution

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Review 1: XPS and Electron Microscopy Study of Oxide-Scale Evolution on Ignition Resistant Mg-3Ca Alloy at Low and High Heating Rates

10.1017/exp.2020.41.pr1 ◽

2020 ◽

Author(s):

Ali Arslan Kaya

Keyword(s):

Electron Microscopy ◽

Oxide Scale ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Heating Rates ◽

High Heating ◽

Scale Evolution

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Effects of Heating Rate on Formation of Globular and Acicular Austenite during Reversion from Martensite

Metals ◽

10.3390/met9020266 ◽

2019 ◽

Vol 9 (2) ◽

pp. 266 ◽

Cited By ~ 3

Author(s):

Xianguang Zhang ◽

Goro Miyamoto ◽

Yuki Toji ◽

Tadashi Furuhara

Keyword(s):

Heating Rate ◽

High Temperatures ◽

The Other ◽

Growth Mode ◽

High Heating Rate ◽

Heating Rates ◽

Other Hand ◽

High Heating ◽

Martensite Matrix

The effects of heating rate on the formation of acicular and globular austenite during reversion from martensite in Fe–2Mn–1.5Si–0.3C alloy have been investigated. It was found that a low heating rate enhanced the formation of acicular austenite, while a high heating rate favored the formation of globular austenite. The growth of acicular γ was accompanied by the partitioning of Mn and Si, while the growth of globular γ was partitionless. DICTRA simulation revealed that there was a transition in growth mode from partitioning to partitionless for the globular austenite with an increase in temperature at high heating rate. High heating rates promoted a reversion that occurred at high temperatures, which made the partitionless growth of globular austenite occur more easily. On the other hand, the severer Mn enrichment into austenite at low heating rate caused Mn depletion in the martensite matrix, which decelerated the reversion kinetics in the later stage and suppressed the formation of globular austenite.

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Effect of Heating Rates and Loading Rates on Mechanical Behaviors of Magnesium Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.686.63 ◽

2011 ◽

Vol 686 ◽

pp. 63-67

Author(s):

Bin Chen ◽

Ji Luo ◽

Quan Yuan ◽

Ding Fei Zhang ◽

Guo Zheng Quan

Keyword(s):

Magnesium Alloy ◽

Heating Rate ◽

Mechanical Response ◽

Testing System ◽

High Heating Rate ◽

Mechanical Behaviors ◽

Heating Rates ◽

Loading Rates ◽

High Heating ◽

Strength And Plasticity

The mechanical response and failure of the specimens of magnesium alloy AZ61 with different heating rates (HR) and loading rates (LR) were investigated by a Gleeble-1500 thermal-mechanical material testing system. It was found that heating rate has markedly effect on the strength and plasticity of the specimens. The higher the heating rate is, the lower the strength and the smaller of the plasticity of the specimens will be. There is the relatively small effect of the loading rates on the strength and plasticity of the specimens. The metallographs of the failed specimens were also observed. It shows that there are many microvoids in the specimens near the fracture sections. These microvoids may come from the local thermal and stress inconsistency under high heating rate and loading rates and degrade the strength and plasticity of the specimens.

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Comparing fast inductive tempering and conventional tempering: Effects on microstructure and mechanical properties

Metallurgical Research & Technology ◽

10.1051/metal/2018015 ◽

2018 ◽

Vol 115 (4) ◽

pp. 407 ◽

Cited By ~ 4

Author(s):

Annika Eggbauer Vieweg ◽

Gerald Ressel ◽

Peter Raninger ◽

Petri Prevedel ◽

Stefan Marsoner ◽

...

Keyword(s):

Mechanical Properties ◽

Impact Energy ◽

Charpy Impact ◽

Heat Treating ◽

Processing Route ◽

High Heating Rate ◽

Heating Rates ◽

High Heating ◽

Tempering Treatment ◽

Carbide Distribution

Induction heating processes are of rising interest within the heat treating industry. Using inductive tempering, a lot of production time can be saved compared to a conventional tempering treatment. However, it is not completely understood how fast inductive processes influence the quenched and tempered microstructure and the corresponding mechanical properties. The aim of this work is to highlight differences between inductive and conventional tempering processes and to suggest a possible processing route which results in optimized microstructures, as well as desirable mechanical properties. Therefore, the present work evaluates the influencing factors of high heating rates to tempering temperatures on the microstructure as well as hardness and Charpy impact energy. To this end, after quenching a 50CrMo4 steel three different induction tempering processes are carried out and the resulting properties are subsequently compared to a conventional tempering process. The results indicate that notch impact energy raises with increasing heating rates to tempering when realizing the same hardness of the samples. The positive effect of high heating rate on toughness is traced back to smaller carbide sizes, as well as smaller carbide spacing and more uniform carbide distribution over the sample.

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