- How the 19 Headings Fit Into Four Examinations
- Why the Percentages Mislead If You Read Them Wrong
- Part 1: Mathematics, Physics and Chemistry
- Part 2: Strength of Materials, Heat and Fluids, Electricity
- Part 3: The Seven Welding-Related Disciplines
- Part 4: Fabrication Through Procedure Qualification
- How the Domains Roll Up Into Your Composite Score
- Reference Materials Allowed Per Part
- Sequencing Your Preparation Around the Domains
- Version Caveat: B5.16:2006 vs. B5.16:2025
- Frequently Asked Questions
- The 19 domains are examination-content headings spread across four separate AWS exams: 3 in Part 1, 3 in Part 2, 7 in Part 3, 6 in Part 4.
- Each domain percentage applies only within its own part and must never be normalized across all 19 headings.
- Part 4 carries 40% of the composite score, yet it is a multiple-choice exam, not a hands-on welding test.
- You need at least 60% on every part and a weighted composite of at least 70% to pass.
How the 19 Headings Fit Into Four Examinations
The AWS Certified Welding Engineer credential is not a single exam with 19 equal slices. It is four separate computer-based examinations delivered through Prometric testing centers, and the "19 content areas" are the official content headings reproduced across those four parts. That distinction shapes everything about how you should read the blueprint. If you are still sorting out the credential itself, start with What Is CWEng Certification? and then return here.
The mapping is fixed:
| Part | Title | Domains | Questions | Answer Time | Book Status |
|---|---|---|---|---|---|
| Part 1 | Basic Science Fundamental | 1-3 | 36 | 2 hours | Closed book |
| Part 2 | Applied Science Fundamental | 4-6 | 27 | 2 hours | Closed book |
| Part 3 | Welding Related Disciplines | 7-13 | 60 | 3 hours (3 h 15 min appointment) | Open book |
| Part 4 | Practical Welding and Related Applications | 14-19 | 40 | 2 h 30 min (3 hour appointment) | Open book |
Across all four parts that totals 163 questions and nine hours thirty minutes of answer time. It is not one continuous sitting, and appointment time runs longer than the answer clock. An on-screen scientific calculator is available on every part, so arithmetic speed matters less than knowing which equation applies.
Why the Percentages Mislead If You Read Them Wrong
Two further subtleties are easy to miss. First, the guide labels the Part 3 and Part 4 percentages as minimum percentages, so a given sitting can lean somewhat heavier on a domain than the displayed figure. Second, the percentages are about question content, while the composite score uses a separate set of part weights. Part 4 contributes 40% to the composite, which is a completely different number from Fabrication's 25% of Part 4. Mixing the two is the single most frequent source of bad study allocation, and it is worth reading CWEng Passing Score 2026: Exactly What You Need to Pass alongside this guide.
Part 1: Mathematics, Physics and Chemistry
Part 1 is the Basic Science Fundamental Examination: 36 multiple-choice questions, two hours, closed book. It is the gateway part, and it must be passed (together with Part 2) before you can move on to Parts 3 and 4.
Domain 1: Mathematics (25%)
The mathematical toolkit underpinning every later calculation. Expect applied problems rather than abstract proofs.
- Algebra, trigonometry and geometry used to resolve forces and dimensions
- Calculus concepts such as rates of change and integration for areas and averages
- Statistics and probability as they relate to variation in welding data
- Unit conversions and dimensional consistency, which the calculator will not fix for you
Domain 2: Physics (50%)
The heaviest single domain in Part 1 and the one most candidates underestimate because it feels "basic."
- Mechanics: forces, moments, work, energy and power
- Thermal physics: heat, temperature, expansion and energy transfer
- Electrical and magnetic fundamentals that return later in arc physics
- Waves, optics and radiation concepts that connect to inspection and safety
Domain 3: Chemistry (25%)
Chemistry here serves metallurgy, shielding gases, fluxes and corrosion.
- Atomic structure, bonding and the periodic table
- Oxidation, reduction and reaction behavior at elevated temperature
- Gas behavior and solution chemistry relevant to welding atmospheres
- Basic corrosion and electrochemical principles
Because Physics alone is half of Part 1, a candidate with a weak physics background can lose the 60% per-part floor even while doing well in the other two domains. For a realistic read on how demanding this part feels, see How Hard Is the CWEng Exam? Complete Difficulty Guide 2026.
Part 2: Strength of Materials, Heat and Fluids, Electricity
Part 2, the Applied Science Fundamental Examination, has 27 multiple-choice questions over two hours, again closed book. Where Part 1 tests the underlying science, Part 2 applies it to engineering situations.
Domain 4: Strength of Materials (40%)
The largest slice of Part 2 and the foundation for weld design later on.
- Stress, strain, modulus and the stress-strain curve
- Axial, bending, torsional and combined loading
- Beam behavior, moments of inertia and section properties
- Fatigue, fracture and failure concepts that return in Domain 11
Domain 5: Heat Transfer and Fluid Mechanics (30%)
Two disciplines combined into one heading, so prepare for both.
- Conduction, convection and radiation, including their role in weld cooling
- Thermal gradients and heat flow in plate and pipe
- Fluid pressure, flow and gas delivery concepts
- Energy balance reasoning applied to welding situations
Domain 6: Electricity (30%)
Circuit and power fundamentals that make the arc-process material in Part 3 far easier.
- Voltage, current, resistance and Ohm's law
- AC and DC behavior, power and energy calculations
- Inductance, capacitance and transformer principles
- Power source characteristics and electrical safety basics
A practical observation: Domains 4 and 5 consume many candidates' prep hours, but Domain 6 often rewards a small investment, since the same concepts reappear when you study power sources and arc behavior in Part 3.
Part 3: The Seven Welding-Related Disciplines
Part 3 is the Welding Related Disciplines Examination: 60 multiple-choice questions, three hours of answer time inside a three-hour-fifteen-minute appointment, open book. Seven domains share the percentages, and they are displayed as minimums.
| Domain | Share of Part 3 | Core Emphasis |
|---|---|---|
| 7: NDE/Weld Discontinuities | 10% | Recognizing discontinuities and matching NDE methods to them |
| 8: Welding Heat Sources and Arc Physics | 20% | How arcs and other heat sources behave and transfer energy |
| 9: Welding Processes and Controls | 20% | Process capabilities, parameters and control methods |
| 10: Welding and Joint Metallurgy | 20% | Weld and heat-affected-zone metallurgy and joint behavior |
| 11: Weld Design | 20% | Joint design, loading, fatigue and sizing of welds |
| 12: Brazing and Soldering | 5% | Filler flow, joint clearance and process selection |
| 13: Safety | 5% | Hazard control for welding operations |
Domains 8 and 9: Arc Physics and Processes
These two reward the electrical groundwork from Part 2.
- Arc characteristics, polarity effects and metal transfer modes
- Constant-current versus constant-voltage power source behavior
- Process selection among SMAW, GMAW, FCAW, GTAW, SAW and others
- Automation, mechanization and process control concepts
Domains 10 and 11: Metallurgy and Weld Design
The intellectual center of welding engineering, and the place where Parts 1 and 2 science becomes engineering judgment.
- Phase transformations, cooling rates, hardenability and heat-affected-zone behavior
- Preheat, interpass temperature and cracking mechanisms
- Residual stress and distortion
- Static and cyclic loading, joint types and weld sizing logic
Domain 7 is small at 10% but pairs naturally with Part 4's inspection material. Brazing and Soldering and Safety are each only 5%, so they are quick wins: low volume, but tightly bounded and therefore very learnable.
Part 4: Fabrication Through Procedure Qualification
Part 4, Practical Welding and Related Applications, has 40 multiple-choice questions with two hours thirty minutes of answer time in a three-hour appointment. Despite the word "Practical," it is a multiple-choice examination, not a hands-on welding performance test. It is also the heaviest contributor to your composite score at 40%.
| Domain | Share of Part 4 |
|---|---|
| 14: Fabrication | 25% |
| 15: Filler Metals | 15% |
| 16: Inspection | 20% |
| 17: Productivity | 10% |
| 18: Welder Performance Qualification | 10% |
| 19: Welding Procedure Qualification | 20% |
Domain 14: Fabrication (25%)
The largest single heading in Part 4.
- Cutting, forming, fit-up and assembly sequencing
- Distortion control and welding sequence decisions
- Fixturing, positioning and shop-floor practicalities
- Preheat, post-weld heat treatment and handling in production
Domains 18 and 19: Qualification
Together these two carry 30% of Part 4 and revolve around the code supplied in the exam.
- Procedure qualification records, essential variables and testing requirements
- Welder performance qualification limits and positions
- How to read and apply the governing code rather than recall it from memory
- Recognizing when a change requires requalification
Domains 15, 16 and 17 round out the part: filler metal selection and classification, inspection practice and acceptance, and productivity considerations such as deposition rates and cost. Filler metals and inspection feed directly from the metallurgy and NDE material in Part 3, so studying them in sequence reinforces both.
How the Domains Roll Up Into Your Composite Score
Passing requires at least 60% on each part and a weighted composite of at least 70%. Under AWS B5.16:2006, which the dated exam guide references, the composite is:
Composite = 0.15 x Part 1 + 0.15 x Part 2 + 0.30 x Part 3 + 0.40 x Part 4
These are score weights, not question-count proportions. Part 4 has only 40 questions, yet it drives 40% of the result. Reported scores are rounded down to a whole percentage, so a 69.9% does not become 70%. A candidate who scrapes 60% on Parts 1 and 2 must make up the difference in Parts 3 and 4, and because of Part 4's weight, strength in qualification, fabrication and inspection can rescue a thin fundamentals score only if the 60% floor is still met on every part. For the retest rules that apply when a part falls short, see CWEng Pass Rate 2026: What the Data Shows.
Key Takeaway
Treat the 60% per-part floor as a hard gate and the 70% composite as the real target. Part 4 and Part 3 together account for 70% of the composite, so applied judgment in the later domains is where the points are concentrated.
Reference Materials Allowed Per Part
Reference rules differ sharply between parts, and they affect how you study each domain.
- Parts 1 and 2: closed book. Equations, constants and conversions must be known or derivable. Only the on-screen scientific calculator is available.
- Part 3: open book with approved hardcopy references, as listed above. Digital copies are not provided.
- Part 4: AWS D1.1/D1.1M:2020, 24th edition, is the only permitted reference. A hardcopy is allowed, and an on-screen, non-searchable PDF is supplied. Do not carry over a different code edition you may have used for another AWS exam.
Because the Part 4 PDF is non-searchable, familiarity with the code's layout matters more than speed with a keyword search. Practice locating qualification tables, essential variable lists and inspection criteria by structure. The Part 3 and Part 4 reference lists are also summarized in our CWEng Cheat Sheet 2026: One-Page Review of Must-Know Facts.
Sequencing Your Preparation Around the Domains
Because Parts 1 and 2 must be passed before Parts 3 and 4, and because you have one year after passing the last of Parts 1 and 2 to apply for Parts 3 and 4, the order of study follows the exam order. AWS does not offer a CWEng preparation seminar, so the schedule below is a self-directed approach tied to domain weights within each part. For broader methods, see CWEng Study Guide 2026: How to Pass on Your First Attempt.
Part 1 Foundation
- Start with Physics (Domain 2) since it is half the part
- Then Mathematics and Chemistry in proportion to their 25% shares
Part 2 Applications
- Strength of Materials first (40%), then Heat Transfer and Fluids, then Electricity
- Sit Parts 1 and 2 while the material is fresh
Part 3 Disciplines
- Arc physics and processes, then metallurgy and weld design
- Tab and annotate your approved hardcopy references
- Finish with Brazing and Soldering, Safety and NDE
Part 4 Practice
- Work through D1.1 qualification clauses until navigation is automatic
- Prioritize Fabrication, Welding Procedure Qualification and Inspection
The timeline is illustrative, not prescribed by AWS. Adjust it to your background: a candidate with a mechanical engineering degree may compress Weeks 1-6, while a technologist coming up through the shop may need to extend them. Your route to eligibility affects this too; see CWEng Requirements 2026: Eligibility, Prerequisites & How to Qualify for the education and experience pathways.
Version Caveat: B5.16:2006 vs. B5.16:2025
Before you build a study plan around this blueprint, obtain AWS confirmation on migration, applicable completion deadlines and your individual eligibility or exemption decisions. Those exemptions include an Engineering Fundamentals/FE-exam route for Parts 1 and 2 and a separate route for a state Professional Engineer license in welding engineering, and AWS approval governs both. Cost planning belongs in the same conversation; the 2026 price list shows Parts 1 and 2 at $665 member/$755 nonmember and Parts 3 and 4 at $705 member/$795 nonmember, with seat fees included, as broken down in CWEng Certification Cost 2026: Complete Pricing Breakdown. Scheduling considerations are covered in CWEng Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
If you want to test yourself against the domain structure before sitting the real exams, the CWEng practice test site lets you drill by topic, and you can return to the main practice question bank as often as you need while you work through each part.
Frequently Asked Questions
No. Each percentage applies only within its own part, so Physics at 50% means half of Part 1, not half of the credential. The percentages must not be normalized across all 19 headings. The composite score uses separate part weights of 15%, 15%, 30% and 40%.
No. Despite its title, Part 4 is a 40-question multiple-choice examination. It tests applied knowledge of fabrication, filler metals, inspection, productivity and qualification, using AWS D1.1/D1.1M:2020 as its only reference.
Physics is the largest at 50% of Part 1. Strength of Materials is 40% of Part 2, and Fabrication is 25% of Part 4. Part 3's largest headings are tied at 20% each, and the guide labels the Part 3 and Part 4 percentages as minimums.
You need at least 60% on each part and a weighted composite of at least 70%. Scores are rounded down to a whole percentage, so there is no rounding up at the margin. See the passing score guide for worked examples.
Not necessarily. The dated exam guide still cites B5.16:2006 and supplies this four-part structure, while AWS also publishes B5.16:2025. Get written confirmation from AWS on migration and deadlines before replacing this scope. For the credential's earning potential once you pass, see the CWEng salary guide and the ROI analysis.