Stainless Steel Material: what is pickling / passivation?

October 7, 2017October 7, 2017 Thanh ( QC ) Nguyen Le

Stainless Steel material: ( refer to other topic: what is stainless steel? ) A metallic alloy (i.e., metal made of multiple elements such as chromium, nickel, and molybdenum) is generally considered to be “stainless” when its chromium content is greater than about 12 percent by weight ( some document mention it is about 10.5% chromium ), with the balance being iron, higher alloyed stainless steels have higher levels of chromium. Chromium provides corrosion resistance to these alloys by forming a thin, adherent, corrosion-resistant oxide film on a clean (e.g., pickled, wire/rotary brushed, or ground) surface (of the alloy). The main … Continue reading Stainless Steel Material: what is pickling / passivation?

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Why Stainless steel rust / corrosion? – Part 2 – Other corrosion.

October 5, 2017October 7, 2017 Thanh ( QC ) Nguyen Le

In Part 1, we know about Pitting corrosion. We will continue with remain one: 2) Crevice ( gap ) corrosion– Stainless steel requires a supply of oxygen to make sure that the passive layer can form on the surface. In very tight crevices, it is not always possible for the oxygen to gain access to the stainless steel surface thereby causing it to be vulnerable to attack. Crevice Corrosion refers to the localized attack on a metal surface at, or immediately adjacent to, the gap or crevice between two joining surfaces. The gap or crevice can be formed between two metals or a … Continue reading Why Stainless steel rust / corrosion? – Part 2 – Other corrosion.

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Why Stainless Steel Rust / Corrosion? – Part 1 – Pitting Corrosion!

October 4, 2017October 6, 2017 Thanh ( QC ) Nguyen Le

Although stainless steel is much more resistant to corrosion than ordinary carbon or alloy steels, sometime we see rust on Stainless steel. It is ‘stain-less’ not ‘stain impossible’. Sometime we see rust on Stainless steel. It means it can corrode. Why??? It has some common forms of corrosion in Stainless steel: Pitting corrosion: (pitting corrosion of stainless steel in a chloride-containing environment) Pitting corrosion is an electrochemical oxidation-reduction (redox) process, which occurs within localized holes (cells) on the surface of metals coated with a passive film. The passive layer on stainless steel can be attacked by certain chemical species. The chloride ion Cl- is the most … Continue reading Why Stainless Steel Rust / Corrosion? – Part 1 – Pitting Corrosion!

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Stainless steel material: what difference between stainless steel and carbon steel?

October 4, 2017October 4, 2017 Thanh ( QC ) Nguyen Le

Selecting an appropriate type of steel for a project is one of the most important decisions to make. However, before deciding between individual grades, you first have to decide what type of steel to use, such as carbon steel or stainless steel. In general, steel is an alloy with Iron being the main element. An alloy is a material made of a mixture of metals or a metal with other elements. These types of alloys are often cheaper and have improved properties. In the case of steel, iron is primarily mixed with carbon and few other elements. Mixing with carbon makes steel stronger, … Continue reading Stainless steel material: what difference between stainless steel and carbon steel?

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Stainless Steel Material: How is stainless steel made?

October 3, 2017October 4, 2017 Thanh ( QC ) Nguyen Le

Stainless steel is known for excellent corrosion resistance. It is an integral part of modern life and is used in a range of applications, including heavy industry, architecture, automotive manufacture, surgery and dentistry. Stainless steel is an iron alloy with added elements such as chromium, nickel, silicon, manganese, nitrogen and carbon. The properties of the final alloy can be fine-tuned by altering the amounts of the various elements. Now we will know How Stainless steel is made? Raw materials: Stainless steel is the most recycled material in the world and it is estimated that 82% of the stainless steel in use today will be recycled … Continue reading Stainless Steel Material: How is stainless steel made?

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Stainless Steel Material: what is stainless steel?

October 2, 2017October 4, 2017 Thanh ( QC ) Nguyen Le

For this topic, we will have a seri about this material type: Stainless steel material. 1. What is Stainless Steel? 2. Corrosion Mechanisms 3. Environmental Factors That Influence Corrosion in Water 4. Construction and Fabrication Influences on Stainless Steel Corrosion 5. Material Handling After Fabrication and During Installation / Stock Materials and Fabrication of Stainless Steel Parts 6. CORROSION RESISTANCE TESTING METHODS 7. UTILITY AND FABRICATOR EXPERIENCES WITH STAINLESS STEEL CORROSION 8. GUIDELINES FOR STAINLESS STEEL USE 9. Other… Okay! Now we start. Are you ready? I. What is Stainless Steel? A metallic alloy (i.e., metal made of multiple elements such as chromium, … Continue reading Stainless Steel Material: what is stainless steel?

API 570 - PI, Metallurgy, WELDING3 Comments

How to view the material certificate? – Part 2

September 27, 2017September 28, 2017 Thanh ( QC ) Nguyen Le

Continue: PART 2 – How to view the certificate??? We will take example for Mill cert’, other cert’ is same procedure. Mill cert: A Certified Mill Test Report (CMTR) is a quality assurance document generated by the raw material manufacturer and provided with the material to intermediate suppliers and ultimately to a finished goods manufacturer. Whether it’s called a CMTR, Mill Test Report (MTR), Mill Certification, Metallurgical Test Report, or similar name, this document provides the end user of the raw material verification that the material received matches the requirements of their order. CMTRs are also used to maintain traceability … Continue reading How to view the material certificate? – Part 2

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How to view the material certificate? – Part 1

September 22, 2017September 27, 2017 Thanh ( QC ) Nguyen Le

Base on EN – 10204 ( version 2004 ) & EN – 10168 ( for steel products ): We will go to know about some points as below: Part 1 – Know about what type of certificate: PART 2 – How to view the certificate: PART 3 – Fake certificate EN10204 HISTORY: EN 10204 originally started off as DIN 50049 which was a German DIN standard specifying the test certificate requirements for metallic products. I. Part 1 – Know about what type of certificate: A. Scope: The EN-10204 specifies the different types of inspection documents supplied to the purchaser, in accordance with … Continue reading How to view the material certificate? – Part 1

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ASM Handbooks – Intro

September 4, 2017September 7, 2017 Thanh ( QC ) Nguyen Le

This topic just general about AMS containing for each Volume: The ASM Handbook® series contains peer-reviewed, trusted information in every area of materials specialization. The series is the industry’s best known and most comprehensive source of information on ferrous and nonferrous metals and materials technology and is packed with over 35,000 pages of articles, illustrations, tables, graphs, specifications and practical examples for today’s engineer. Volume 1A: Cast Iron Science and Technology (scheduled release: July 31, 2017) Volume 1: Properties and Selection: Irons, Steels, and High-Performance Alloys Volume 2: Properties and Selection: Nonferrous Alloys and Special-Purpose Materials Volume 3: Alloy Phase … Continue reading ASM Handbooks – Intro