01
Grades & comparisons
201 vs 304 Stainless Steel: Selection and Buying Controls
A service-aware comparison that prevents price-only substitution.
Source-led metal knowledge
Metal knowledge and procurement Blog
Practical answers, dimensional guides, comparisons and buying frameworks connect real search questions to reviewed material authority and orderable products.
Published library
18 bilingual technical and buying guides
Every guide includes an answer first, decision table, limitations, buying checklist, sources and an attributable on-page inquiry path.
Metal basicsGrades & comparisonsDimensions & standardsBuying guides
02
Grades & comparisons
304 vs 304L Stainless Steel: When Low Carbon Matters
A welding- and specification-aware choice for coil, sheet and fabrication.
03
Grades & comparisons
316 vs 316L Stainless Steel: Corrosion, Welding and RFQ
Distinguish the two molybdenum-bearing grades without using grade name as the whole specification.
04
Grades & comparisons
PPGI vs PPGL Steel Coil: Substrate, Coating System and RFQ
Specify metallic substrate and paint system separately for comparable roofing and cladding quotations.
05
Grades & comparisons
G60 vs G90 Galvanized Steel Coil: Coating Designations Explained
Read continuous-sheet coating designations correctly before specifying coil for exterior or formed products.
06
Grades & comparisons
5052 vs 6061 Aluminum: Sheet Selection, Forming and Procurement
Compare a 5xxx sheet alloy with a widely used 6xxx alloy by form, temper and fabrication.
07
Metal basics
Does Stainless Steel Rust? Causes, Grades and Prevention
Why stainless can stain or corrode, and how environment, grade, finish, fabrication and maintenance change the result.
08
Metal basics
Does Aluminum Rust? Oxidation, Corrosion and Alloy Selection
Aluminum does not form iron rust, but it can oxidize, pit, stain and corrode when alloy, environment and detailing are mismatched.
09
Metal basics
Which Metals Do Not Rust? A Corrosion-Resistance Comparison
A practical comparison of stainless steel, aluminum, copper alloys and coated steel by environment, failure mode and purchasing implication.
10
Dimensions & standards
Sheet Metal Gauge Chart: Gauge, Inches and Millimeters
Why the same gauge number can mean different thicknesses for steel, galvanized steel, stainless steel and aluminum.
11
Dimensions & standards
Stainless Steel Pipe Sizes and Schedules
How NPS, DN, outside diameter, Schedule, wall thickness and product specification fit together.
12
Dimensions & standards
Stainless Steel Tube Sizes and Wall Thickness
How tube OD, wall, tolerance, manufacturing route and service specification differ from pipe ordering.
13
Grades & comparisons
304 vs 316 Stainless Steel: Properties, Corrosion and Selection
A decision-led comparison of molybdenum, chloride resistance, fabrication, standards and procurement—not a claim that one grade is always better.
14
Grades & comparisons
Stainless Steel Pipe vs Tube: Dimensions, Standards and Buying
Pipe and tube are purchasing systems, not interchangeable labels: their dimensional logic, standards, tolerances and end uses differ.
15
Grades & comparisons
Seamless vs Welded Steel Pipe: Selection and Procurement
Manufacturing route must follow the governing specification, service, dimensions, inspection and economics—not a universal quality ranking.
16
Grades & comparisons
6061 vs 7075 Aluminum: Strength, Corrosion and Machining
A product- and temper-aware comparison for engineering screening and procurement.
17
Buying guides
How to Choose a Stainless Steel Coil Supplier in China
A supplier-qualification and RFQ framework covering mill source, grade, dimensions, finish, slitting, testing, packing and traceability.
18
Buying guides
Galvanized Steel Pipe Procurement Guide
Specify the base pipe, galvanizing route, coating acceptance, threads/ends, tests, documents and packing as one supply package.